[{"publisher":"American Physical Society","title":"Orbital Chern insulator states in twisted monolayer-bilayer graphene and electrical switching of topological and magnetic order","language":[{"iso":"eng"}],"month":"03","year":"2021","date_published":"2021-03-01T00:00:00Z","conference":{"start_date":"2021-03-15","end_date":"2021-03-19","location":"Virtual","name":"APS: American Physical Society"},"date_created":"2022-01-27T09:49:48Z","alternative_title":["Bulletin of the American Physical Society"],"article_number":"E42.00010","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR21/Session/E42.10"}],"abstract":[{"lang":"eng","text":"We experimentally investigate narrow and topologically nontrivial moiré minibands hosted by van der Waals heterostructures consisting of a graphene monolayer rotationally faulted with respect to a Bernal-stacked bilayer. At fillings ν= 1 and 3 electrons per moiré unit cell within these bands, we observe quantized anomalous Hall effects with Rxy≈h/2e2, indicative of spontaneous polarization of the system into a single valley-projected band with Chern number C= 2. Remarkably, we also observe the evidence of symmetry broken Chern insulator states at ν= 1.5 and 3.5. At ν= 3 we find that the sign of the quantum anomalous Hall effect can be reversed via field-effect control of the chemical potential. This curious effect arises from the magnetization contribution due to topological edge states, which drive a reversal of the total magnetization and thus a switch of the favored magnetic state. Remarkably, we find that this switch is hysteretic, which we use to demonstrate non-volatile electric-field-induced reversal of the magnetic state. Voltage control of magnetic states can be used to electrically pattern nonvolatile magnetic domain structures hosting chiral edge states, with applications ranging from reconfigurable microwave circuit elements to ultra-low-power magnetic memory."}],"intvolume":"        66","author":[{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","first_name":"Hryhoriy"},{"full_name":"Zhu, Jihang","last_name":"Zhu","first_name":"Jihang"},{"full_name":"Kumar, Manish","last_name":"Kumar","first_name":"Manish"},{"full_name":"Zhang, Yuxuan","last_name":"Zhang","first_name":"Yuxuan"},{"first_name":"Fangyuan","full_name":"Yang, Fangyuan","last_name":"Yang"},{"last_name":"Tschirhart","full_name":"Tschirhart, Charles","first_name":"Charles"},{"first_name":"Marec","full_name":"Serlin, Marec","last_name":"Serlin"},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"last_name":"Tanaguchi","full_name":"Tanaguchi, Takashi","first_name":"Takashi"},{"first_name":"Allan","last_name":"MacDonald","full_name":"MacDonald, Allan"},{"first_name":"Andrea","last_name":"Young","full_name":"Young, Andrea"}],"status":"public","day":"01","citation":{"chicago":"Polshyn, Hryhoriy, Jihang Zhu, Manish Kumar, Yuxuan Zhang, Fangyuan Yang, Charles Tschirhart, Marec Serlin, et al. “Orbital Chern Insulator States in Twisted Monolayer-Bilayer Graphene and Electrical Switching of Topological and Magnetic Order.” In <i>APS March Meeting 2021</i>, Vol. 66. American Physical Society, 2021.","ieee":"H. Polshyn <i>et al.</i>, “Orbital Chern insulator states in twisted monolayer-bilayer graphene and electrical switching of topological and magnetic order,” in <i>APS March Meeting 2021</i>, Virtual, 2021, vol. 66, no. 1.","apa":"Polshyn, H., Zhu, J., Kumar, M., Zhang, Y., Yang, F., Tschirhart, C., … Young, A. (2021). Orbital Chern insulator states in twisted monolayer-bilayer graphene and electrical switching of topological and magnetic order. In <i>APS March Meeting 2021</i> (Vol. 66). Virtual: American Physical Society.","short":"H. Polshyn, J. Zhu, M. Kumar, Y. Zhang, F. Yang, C. Tschirhart, M. Serlin, K. Watanabe, T. Tanaguchi, A. MacDonald, A. Young, in:, APS March Meeting 2021, American Physical Society, 2021.","ista":"Polshyn H, Zhu J, Kumar M, Zhang Y, Yang F, Tschirhart C, Serlin M, Watanabe K, Tanaguchi T, MacDonald A, Young A. 2021. Orbital Chern insulator states in twisted monolayer-bilayer graphene and electrical switching of topological and magnetic order. APS March Meeting 2021. APS: American Physical Society, Bulletin of the American Physical Society, vol. 66, E42.00010.","ama":"Polshyn H, Zhu J, Kumar M, et al. Orbital Chern insulator states in twisted monolayer-bilayer graphene and electrical switching of topological and magnetic order. In: <i>APS March Meeting 2021</i>. Vol 66. American Physical Society; 2021.","mla":"Polshyn, Hryhoriy, et al. “Orbital Chern Insulator States in Twisted Monolayer-Bilayer Graphene and Electrical Switching of Topological and Magnetic Order.” <i>APS March Meeting 2021</i>, vol. 66, no. 1, E42.00010, American Physical Society, 2021."},"type":"conference","_id":"10692","extern":"1","publication_identifier":{"issn":["0003-0503"]},"user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","quality_controlled":"1","oa_version":"Published Version","issue":"1","publication":"APS March Meeting 2021","volume":66,"oa":1,"date_updated":"2022-01-27T10:46:23Z","article_processing_charge":"No"},{"external_id":{"pmid":["34045322"],"arxiv":["2006.08053"]},"title":"Imaging orbital ferromagnetism in a moiré Chern insulator","year":"2021","doi":"10.1126/science.abd3190","main_file_link":[{"url":"https://arxiv.org/abs/2006.08053","open_access":"1"}],"abstract":[{"lang":"eng","text":"Electrons in moiré flat band systems can spontaneously break time-reversal symmetry, giving rise to a quantized anomalous Hall effect. In this study, we use a superconducting quantum interference device to image stray magnetic fields in twisted bilayer graphene aligned to hexagonal boron nitride. We find a magnetization of several Bohr magnetons per charge carrier, demonstrating that the magnetism is primarily orbital in nature. Our measurements reveal a large change in the magnetization as the chemical potential is swept across the quantum anomalous Hall gap, consistent with the expected contribution of chiral edge states to the magnetization of an orbital Chern insulator. Mapping the spatial evolution of field-driven magnetic reversal, we find a series of reproducible micrometer-scale domains pinned to structural disorder."}],"keyword":["multidisciplinary"],"author":[{"full_name":"Tschirhart, C. L.","last_name":"Tschirhart","first_name":"C. L."},{"last_name":"Serlin","full_name":"Serlin, M.","first_name":"M."},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","first_name":"Hryhoriy","last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896"},{"last_name":"Shragai","full_name":"Shragai, A.","first_name":"A."},{"first_name":"Z.","full_name":"Xia, Z.","last_name":"Xia"},{"first_name":"J.","full_name":"Zhu, J.","last_name":"Zhu"},{"full_name":"Zhang, Y.","last_name":"Zhang","first_name":"Y."},{"first_name":"K.","full_name":"Watanabe, K.","last_name":"Watanabe"},{"first_name":"T.","last_name":"Taniguchi","full_name":"Taniguchi, T."},{"full_name":"Huber, M. E.","last_name":"Huber","first_name":"M. E."},{"full_name":"Young, A. F.","last_name":"Young","first_name":"A. F."}],"publication_status":"published","citation":{"mla":"Tschirhart, C. L., et al. “Imaging Orbital Ferromagnetism in a Moiré Chern Insulator.” <i>Science</i>, vol. 372, no. 6548, American Association for the Advancement of Science, 2021, pp. 1323–27, doi:<a href=\"https://doi.org/10.1126/science.abd3190\">10.1126/science.abd3190</a>.","ama":"Tschirhart CL, Serlin M, Polshyn H, et al. Imaging orbital ferromagnetism in a moiré Chern insulator. <i>Science</i>. 2021;372(6548):1323-1327. doi:<a href=\"https://doi.org/10.1126/science.abd3190\">10.1126/science.abd3190</a>","short":"C.L. Tschirhart, M. Serlin, H. Polshyn, A. Shragai, Z. Xia, J. Zhu, Y. Zhang, K. Watanabe, T. Taniguchi, M.E. Huber, A.F. Young, Science 372 (2021) 1323–1327.","ista":"Tschirhart CL, Serlin M, Polshyn H, Shragai A, Xia Z, Zhu J, Zhang Y, Watanabe K, Taniguchi T, Huber ME, Young AF. 2021. Imaging orbital ferromagnetism in a moiré Chern insulator. Science. 372(6548), 1323–1327.","apa":"Tschirhart, C. L., Serlin, M., Polshyn, H., Shragai, A., Xia, Z., Zhu, J., … Young, A. F. (2021). Imaging orbital ferromagnetism in a moiré Chern insulator. <i>Science</i>. American Association for the Advancement of Science. <a href=\"https://doi.org/10.1126/science.abd3190\">https://doi.org/10.1126/science.abd3190</a>","ieee":"C. L. Tschirhart <i>et al.</i>, “Imaging orbital ferromagnetism in a moiré Chern insulator,” <i>Science</i>, vol. 372, no. 6548. American Association for the Advancement of Science, pp. 1323–1327, 2021.","chicago":"Tschirhart, C. L., M. Serlin, Hryhoriy Polshyn, A. Shragai, Z. Xia, J. Zhu, Y. Zhang, et al. “Imaging Orbital Ferromagnetism in a Moiré Chern Insulator.” <i>Science</i>. American Association for the Advancement of Science, 2021. <a href=\"https://doi.org/10.1126/science.abd3190\">https://doi.org/10.1126/science.abd3190</a>."},"pmid":1,"_id":"10616","publication_identifier":{"eissn":["1095-9203"],"issn":["0036-8075"]},"extern":"1","acknowledgement":"We thank A. H. Macdonald, J. Zhu, M. Zaletel, and D. Xiao for discussions of the results and E. Lachman for comments on the manuscript. Funding: The work was primarily funded by the US Department of Energy under DE-SC0020043, with additional support for instrumentation development supported by the Army Research Office under grant W911NF-16-1-0361. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by MEXT, Japan, grant JPMXP0112101001; JSPS KAKENHI grant JP20H00354 and CREST grant JPMJCR15F3, JST. C.L.T. acknowledges support from the Hertz Foundation and from the National Science Foundation Graduate Research Fellowship Program under grant 1650114. This project is funded in part by the Gordon and Betty Moore Foundation’s EPiQS Initiative, grant GBMF9471 to A.F.Y.","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","quality_controlled":"1","oa_version":"Preprint","arxiv":1,"oa":1,"date_updated":"2022-01-13T14:11:36Z","volume":372,"article_processing_charge":"No","publisher":"American Association for the Advancement of Science","scopus_import":"1","language":[{"iso":"eng"}],"month":"05","date_published":"2021-05-27T00:00:00Z","article_type":"original","date_created":"2022-01-13T12:17:45Z","intvolume":"       372","status":"public","day":"27","type":"journal_article","issue":"6548","publication":"Science","page":"1323-1327"},{"date_created":"2022-01-13T12:30:47Z","article_type":"original","date_published":"2021-12-09T00:00:00Z","month":"12","language":[{"iso":"eng"}],"scopus_import":"1","publisher":"Springer Nature","publication":"Nature Physics","type":"journal_article","day":"09","status":"public","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2104.01178"}],"year":"2021","doi":"10.1038/s41567-021-01418-6","title":"Topological charge density waves at half-integer filling of a moiré superlattice","external_id":{"arxiv":["2104.01178"]},"article_processing_charge":"No","date_updated":"2022-01-13T14:11:31Z","oa":1,"arxiv":1,"quality_controlled":"1","oa_version":"Preprint","acknowledgement":"We are grateful to J. Zhu for fruitful discussions. A.F.Y. acknowledges support from the Office of Naval Research under award N00014-20-1-2609, and the Gordon and Betty Moore Foundation under award GBMF9471. M.P.Z. acknowledges support from the ARO under MURI W911NF-16-1-0361. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan, via grant no. JPMXP0112101001; JSPS KAKENHI grant no. JP20H00354; and the CREST(JPMJCR15F3), JST. A.V. was supported by a Simons Investigator Award. P.L. was supported by the Department of Defense (DoD) through the National Defense Science and Engineering Graduate Fellowship (NDSEG) Program.","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","publication_identifier":{"issn":["1745-2473"],"eissn":["1745-2481"]},"extern":"1","_id":"10617","citation":{"chicago":"Polshyn, Hryhoriy, Y. Zhang, M. A. Kumar, T. Soejima, P. Ledwith, K. Watanabe, T. Taniguchi, A. Vishwanath, M. P. Zaletel, and A. F. Young. “Topological Charge Density Waves at Half-Integer Filling of a Moiré Superlattice.” <i>Nature Physics</i>. Springer Nature, 2021. <a href=\"https://doi.org/10.1038/s41567-021-01418-6\">https://doi.org/10.1038/s41567-021-01418-6</a>.","ieee":"H. Polshyn <i>et al.</i>, “Topological charge density waves at half-integer filling of a moiré superlattice,” <i>Nature Physics</i>. Springer Nature, 2021.","apa":"Polshyn, H., Zhang, Y., Kumar, M. A., Soejima, T., Ledwith, P., Watanabe, K., … Young, A. F. (2021). Topological charge density waves at half-integer filling of a moiré superlattice. <i>Nature Physics</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41567-021-01418-6\">https://doi.org/10.1038/s41567-021-01418-6</a>","ista":"Polshyn H, Zhang Y, Kumar MA, Soejima T, Ledwith P, Watanabe K, Taniguchi T, Vishwanath A, Zaletel MP, Young AF. 2021. Topological charge density waves at half-integer filling of a moiré superlattice. Nature Physics.","short":"H. Polshyn, Y. Zhang, M.A. Kumar, T. Soejima, P. Ledwith, K. Watanabe, T. Taniguchi, A. Vishwanath, M.P. Zaletel, A.F. Young, Nature Physics (2021).","ama":"Polshyn H, Zhang Y, Kumar MA, et al. Topological charge density waves at half-integer filling of a moiré superlattice. <i>Nature Physics</i>. 2021. doi:<a href=\"https://doi.org/10.1038/s41567-021-01418-6\">10.1038/s41567-021-01418-6</a>","mla":"Polshyn, Hryhoriy, et al. “Topological Charge Density Waves at Half-Integer Filling of a Moiré Superlattice.” <i>Nature Physics</i>, Springer Nature, 2021, doi:<a href=\"https://doi.org/10.1038/s41567-021-01418-6\">10.1038/s41567-021-01418-6</a>."},"publication_status":"published","author":[{"orcid":"0000-0001-8223-8896","last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","first_name":"Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"first_name":"Y.","full_name":"Zhang, Y.","last_name":"Zhang"},{"full_name":"Kumar, M. A.","last_name":"Kumar","first_name":"M. A."},{"full_name":"Soejima, T.","last_name":"Soejima","first_name":"T."},{"first_name":"P.","last_name":"Ledwith","full_name":"Ledwith, P."},{"last_name":"Watanabe","full_name":"Watanabe, K.","first_name":"K."},{"last_name":"Taniguchi","full_name":"Taniguchi, T.","first_name":"T."},{"first_name":"A.","last_name":"Vishwanath","full_name":"Vishwanath, A."},{"full_name":"Zaletel, M. P.","last_name":"Zaletel","first_name":"M. P."},{"full_name":"Young, A. F.","last_name":"Young","first_name":"A. F."}],"keyword":["general physics","astronomy"],"abstract":[{"text":"When a flat band is partially filled with electrons, strong Coulomb interactions between them may lead to the emergence of topological gapped states with quantized Hall conductivity. Such emergent topological states have been found in partially filled Landau levels1 and Hofstadter bands2,3; however, in both cases, a large magnetic field is required to produce the underlying flat band. The recent observation of quantum anomalous Hall effects in narrow-band moiré materials4,5,6,7 has led to the theoretical prediction that such phases could be realized at zero magnetic field8,9,10,11,12. Here we report the observation of insulators with Chern number C = 1 in the zero-magnetic-field limit at half-integer filling of the moiré superlattice unit cell in twisted monolayer–bilayer graphene7,13,14,15. Chern insulators in a half-filled band suggest the spontaneous doubling of the superlattice unit cell2,3,16, and our calculations find a ground state of the topological charge density wave at half-filling of the underlying band. The discovery of these topological phases at fractional superlattice filling enables the further pursuit of zero-magnetic-field phases that have fractional statistics that exist either as elementary excitations or bound to lattice dislocations.","lang":"eng"}]},{"abstract":[{"lang":"eng","text":"Harnessing the properties of vortices in superconductors is crucial for fundamental science and technological applications; thus, it has been an ongoing goal to locally probe and control vortices. Here, we use a scanning probe technique that enables studies of vortex dynamics in superconducting systems by leveraging the resonant behavior of a raster-scanned, magnetic-tipped cantilever. This experimental setup allows us to image and control vortices, as well as extract key energy scales of the vortex interactions. Applying this technique to lattices of superconductor island arrays on a metal, we obtain a variety of striking spatial patterns that encode information about the energy landscape for vortices in the system. We interpret these patterns in terms of local vortex dynamics and extract the relative strengths of the characteristic energy scales in the system, such as the vortex-magnetic field and vortex-vortex interaction strengths, as well as the vortex chemical potential. We also demonstrate that the relative strengths of the interactions can be tuned and show how these interactions shift with an applied bias. The high degree of tunability and local nature of such vortex imaging and control not only enable new understanding of vortex interactions, but also have potential applications in more complex systems such as those relevant to quantum computing."}],"author":[{"full_name":"Naibert, Tyler R.","last_name":"Naibert","first_name":"Tyler R."},{"first_name":"Hryhoriy","last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"last_name":"Garrido-Menacho","full_name":"Garrido-Menacho, Rita","first_name":"Rita"},{"last_name":"Durkin","full_name":"Durkin, Malcolm","first_name":"Malcolm"},{"first_name":"Brian","full_name":"Wolin, Brian","last_name":"Wolin"},{"first_name":"Victor","last_name":"Chua","full_name":"Chua, Victor"},{"first_name":"Ian","last_name":"Mondragon-Shem","full_name":"Mondragon-Shem, Ian"},{"first_name":"Taylor","last_name":"Hughes","full_name":"Hughes, Taylor"},{"first_name":"Nadya","last_name":"Mason","full_name":"Mason, Nadya"},{"last_name":"Budakian","full_name":"Budakian, Raffi","first_name":"Raffi"}],"publication_status":"published","citation":{"mla":"Naibert, Tyler R., et al. “Imaging and Controlling Vortex Dynamics in Mesoscopic Superconductor-Normal-Metal-Superconductor Arrays.” <i>Physical Review B</i>, vol. 103, no. 22, 224526, American Physical Society, 2021, doi:<a href=\"https://doi.org/10.1103/physrevb.103.224526\">10.1103/physrevb.103.224526</a>.","ama":"Naibert TR, Polshyn H, Garrido-Menacho R, et al. Imaging and controlling vortex dynamics in mesoscopic superconductor-normal-metal-superconductor arrays. <i>Physical Review B</i>. 2021;103(22). doi:<a href=\"https://doi.org/10.1103/physrevb.103.224526\">10.1103/physrevb.103.224526</a>","short":"T.R. Naibert, H. Polshyn, R. Garrido-Menacho, M. Durkin, B. Wolin, V. Chua, I. Mondragon-Shem, T. Hughes, N. Mason, R. Budakian, Physical Review B 103 (2021).","ista":"Naibert TR, Polshyn H, Garrido-Menacho R, Durkin M, Wolin B, Chua V, Mondragon-Shem I, Hughes T, Mason N, Budakian R. 2021. Imaging and controlling vortex dynamics in mesoscopic superconductor-normal-metal-superconductor arrays. Physical Review B. 103(22), 224526.","ieee":"T. R. Naibert <i>et al.</i>, “Imaging and controlling vortex dynamics in mesoscopic superconductor-normal-metal-superconductor arrays,” <i>Physical Review B</i>, vol. 103, no. 22. American Physical Society, 2021.","apa":"Naibert, T. R., Polshyn, H., Garrido-Menacho, R., Durkin, M., Wolin, B., Chua, V., … Budakian, R. (2021). Imaging and controlling vortex dynamics in mesoscopic superconductor-normal-metal-superconductor arrays. <i>Physical Review B</i>. American Physical Society. <a href=\"https://doi.org/10.1103/physrevb.103.224526\">https://doi.org/10.1103/physrevb.103.224526</a>","chicago":"Naibert, Tyler R., Hryhoriy Polshyn, Rita Garrido-Menacho, Malcolm Durkin, Brian Wolin, Victor Chua, Ian Mondragon-Shem, Taylor Hughes, Nadya Mason, and Raffi Budakian. “Imaging and Controlling Vortex Dynamics in Mesoscopic Superconductor-Normal-Metal-Superconductor Arrays.” <i>Physical Review B</i>. American Physical Society, 2021. <a href=\"https://doi.org/10.1103/physrevb.103.224526\">https://doi.org/10.1103/physrevb.103.224526</a>."},"_id":"10649","publication_identifier":{"issn":["2469-9950"],"eissn":["2469-9969"]},"extern":"1","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","acknowledgement":"This work was supported by the Department of Energy (DOE) Basic Energy Sciences under Grant No. DE-SC0012649 and the National Science Foundation (NSF) under Grant No. DMR 17-10437. V.C. was supported by the Gordon and Betty Moore Foundation EPiQS Initiative through Grant No. GBMF4305. N.M. also acknowledges support from DOE-EFRC under Grant No. DE-SC0021238 for analysis/manuscript preparation. This research was carried out in part in the Materials Research Laboratory Central Research Facilities, University of Illinois.","quality_controlled":"1","oa_version":"Preprint","arxiv":1,"volume":103,"oa":1,"date_updated":"2022-01-24T08:25:18Z","article_processing_charge":"No","title":"Imaging and controlling vortex dynamics in mesoscopic superconductor-normal-metal-superconductor arrays","external_id":{"arxiv":["1705.08956"]},"year":"2021","doi":"10.1103/physrevb.103.224526","main_file_link":[{"url":"https://arxiv.org/abs/1705.08956","open_access":"1"}],"article_number":"224526","intvolume":"       103","status":"public","day":"24","type":"journal_article","issue":"22","publication":"Physical Review B","publisher":"American Physical Society","language":[{"iso":"eng"}],"month":"06","article_type":"original","date_published":"2021-06-24T00:00:00Z","date_created":"2022-01-20T09:39:40Z"},{"alternative_title":["Bulletin of the American Physical Society"],"main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR21/Session/L42.12"}],"article_number":"L42.00012","year":"2021","title":"Probing orbital Chern ferromagnet phase in twisted bilayer graphene","volume":66,"oa":1,"date_updated":"2022-01-27T09:37:51Z","article_processing_charge":"No","_id":"10651","extern":"1","publication_identifier":{"issn":["0003-0503"]},"acknowledgement":"I acknowledge and appreciate support from the Hertz Foundation and from the National Science Foundation Graduate Research Fellowship Program under grant 1650114.","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","oa_version":"None","quality_controlled":"1","publication_status":"published","citation":{"chicago":"Tschirhart, Charles, Marec Serlin, Hryhoriy Polshyn, Avi G. Shragai, Zhengchao Xia, Jiacheng Zhu, Yuxuan Zhang, et al. “Probing Orbital Chern Ferromagnet Phase in Twisted Bilayer Graphene.” In <i>APS March Meeting 2021</i>, Vol. 66. American Physical Society, 2021.","apa":"Tschirhart, C., Serlin, M., Polshyn, H., Shragai, A. G., Xia, Z., Zhu, J., … Young, A. (2021). Probing orbital Chern ferromagnet phase in twisted bilayer graphene. In <i>APS March Meeting 2021</i> (Vol. 66). Virtual, United States: American Physical Society.","ieee":"C. Tschirhart <i>et al.</i>, “Probing orbital Chern ferromagnet phase in twisted bilayer graphene,” in <i>APS March Meeting 2021</i>, Virtual, United States, 2021, vol. 66, no. 1.","ista":"Tschirhart C, Serlin M, Polshyn H, Shragai AG, Xia Z, Zhu J, Zhang Y, Watanabe K, Taniguchi T, Huber ME, Young A. 2021. Probing orbital Chern ferromagnet phase in twisted bilayer graphene. APS March Meeting 2021. APS: American Physical Society, Bulletin of the American Physical Society, vol. 66, L42.00012.","short":"C. Tschirhart, M. Serlin, H. Polshyn, A.G. Shragai, Z. Xia, J. Zhu, Y. Zhang, K. Watanabe, T. Taniguchi, M.E. Huber, A. Young, in:, APS March Meeting 2021, American Physical Society, 2021.","ama":"Tschirhart C, Serlin M, Polshyn H, et al. Probing orbital Chern ferromagnet phase in twisted bilayer graphene. In: <i>APS March Meeting 2021</i>. Vol 66. American Physical Society; 2021.","mla":"Tschirhart, Charles, et al. “Probing Orbital Chern Ferromagnet Phase in Twisted Bilayer Graphene.” <i>APS March Meeting 2021</i>, vol. 66, no. 1, L42.00012, American Physical Society, 2021."},"abstract":[{"lang":"eng","text":"Electrons in the moiré flat bands of magic angle twisted bilayer graphene aligned to hexagonal boron nitride can break time reversal symmetry and open an interaction-driven, topological gap. The resulting magnetic order and associated quantized anomalous Hall effect have properties that diverge substantially from quantized anomalous Hall effects observed in other systems. I will present transport data and scanning probe magnetometry data acquired using a nanoSQUID-on-tip microscope. A quantitative analysis of the magnitude of the magnetization of the Chern magnet shows that the magnetic moment per moiré unit cell substantially exceeds 1 μB and grows rapidly in the topological gap, consistent with an orbital origin for the magnetic order. We find that the Barkhausen jumps observed in transport measurements can be mapped directly to microscopic motion of ferromagnetic domain walls. These domain walls are strongly pinned to disorder in the device and are reproducible across thermal cycles, suggesting coupling between the magnetic degrees of freedom and structural inhomogeneity."}],"author":[{"last_name":"Tschirhart","full_name":"Tschirhart, Charles","first_name":"Charles"},{"first_name":"Marec","last_name":"Serlin","full_name":"Serlin, Marec"},{"orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn","first_name":"Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"first_name":"Avi G.","full_name":"Shragai, Avi G.","last_name":"Shragai"},{"first_name":"Zhengchao","last_name":"Xia","full_name":"Xia, Zhengchao"},{"full_name":"Zhu, Jiacheng","last_name":"Zhu","first_name":"Jiacheng"},{"last_name":"Zhang","full_name":"Zhang, Yuxuan","first_name":"Yuxuan"},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"first_name":"Takashi","last_name":"Taniguchi","full_name":"Taniguchi, Takashi"},{"full_name":"Huber, Martin E.","last_name":"Huber","first_name":"Martin E."},{"first_name":"Andrea","full_name":"Young, Andrea","last_name":"Young"}],"conference":{"start_date":"2021-03-15","end_date":"2021-03-19","location":"Virtual, United States","name":"APS: American Physical Society"},"date_created":"2022-01-20T15:43:16Z","month":"03","date_published":"2021-03-01T00:00:00Z","publisher":"American Physical Society","language":[{"iso":"eng"}],"issue":"1","publication":"APS March Meeting 2021","day":"01","type":"conference","intvolume":"        66","status":"public"},{"type":"conference","day":"01","status":"public","intvolume":"        65","publication":"APS March Meeting 2020","issue":"1","date_published":"2020-03-01T00:00:00Z","month":"03","language":[{"iso":"eng"}],"publisher":"American Physical Society","date_created":"2022-01-27T10:50:10Z","conference":{"location":"Denver, CO, United States","end_date":"2020-03-06","name":"APS: American Physical Society","start_date":"2020-03-02"},"citation":{"chicago":"Zhou, Haoxin, Hryhoriy Polshyn, Takashi Tanaguchi, Kenji Watanabe, and Andrea Young. “Sublattice Resolved Spin Wave Transport through Graphene Fractional Quantum Hall States as a Probe of Isospin Order.” In <i>APS March Meeting 2020</i>, Vol. 65. American Physical Society, 2020.","ieee":"H. Zhou, H. Polshyn, T. Tanaguchi, K. Watanabe, and A. Young, “Sublattice resolved spin wave transport through graphene fractional quantum Hall states as a probe of isospin order,” in <i>APS March Meeting 2020</i>, Denver, CO, United States, 2020, vol. 65, no. 1.","apa":"Zhou, H., Polshyn, H., Tanaguchi, T., Watanabe, K., &#38; Young, A. (2020). Sublattice resolved spin wave transport through graphene fractional quantum Hall states as a probe of isospin order. In <i>APS March Meeting 2020</i> (Vol. 65). Denver, CO, United States: American Physical Society.","short":"H. Zhou, H. Polshyn, T. Tanaguchi, K. Watanabe, A. Young, in:, APS March Meeting 2020, American Physical Society, 2020.","ista":"Zhou H, Polshyn H, Tanaguchi T, Watanabe K, Young A. 2020. Sublattice resolved spin wave transport through graphene fractional quantum Hall states as a probe of isospin order. APS March Meeting 2020. APS: American Physical Society, Bulletin of the American Physical Society, vol. 65, B54. 00007.","ama":"Zhou H, Polshyn H, Tanaguchi T, Watanabe K, Young A. Sublattice resolved spin wave transport through graphene fractional quantum Hall states as a probe of isospin order. In: <i>APS March Meeting 2020</i>. Vol 65. American Physical Society; 2020.","mla":"Zhou, Haoxin, et al. “Sublattice Resolved Spin Wave Transport through Graphene Fractional Quantum Hall States as a Probe of Isospin Order.” <i>APS March Meeting 2020</i>, vol. 65, no. 1, B54. 00007, American Physical Society, 2020."},"publication_status":"published","author":[{"first_name":"Haoxin","last_name":"Zhou","full_name":"Zhou, Haoxin"},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","first_name":"Hryhoriy"},{"full_name":"Tanaguchi, Takashi","last_name":"Tanaguchi","first_name":"Takashi"},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"full_name":"Young, Andrea","last_name":"Young","first_name":"Andrea"}],"abstract":[{"text":"High quality graphene heterostructures host an array of fractional quantum Hall isospin ferromagnets with diverse spin and valley orders. While a variety of phase transitions have been observed, disentangling the isospin phase diagram of these states is hampered by the absence of direct probes of spin and valley order. I will describe nonlocal transport measurements based on launching spin waves from a gate defined lateral heterojunction, performed in ultra-clean Corbino geometry graphene devices. At high magnetic fields, we find that the spin-wave transport signal is detected in all FQH states between ν = 0 and 1; however, between ν = 1 and 2 only odd numerator FQH states show finite nonlocal transport, despite the identical ground state spin polarizations in odd- and even numerator states. The results reveal that the neutral spin-waves are both spin and sublattice polarized making them a sensitive probe of ground state sublattice structure. Armed with this understanding, we use nonlocal transport signal to a magnetic field tuned isospin phase transition, showing that the emergent even denominator state at ν = 1/2 in monolayer graphene is indeed a multicomponent state featuring equal populations on each sublattice.","lang":"eng"}],"article_processing_charge":"No","oa":1,"date_updated":"2022-01-27T10:58:38Z","volume":65,"quality_controlled":"1","oa_version":"Published Version","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","publication_identifier":{"issn":["0003-0503"]},"extern":"1","_id":"10693","year":"2020","title":"Sublattice resolved spin wave transport through graphene fractional quantum Hall states as a probe of isospin order","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR20/Session/B54.7"}],"article_number":"B54. 00007","alternative_title":["Bulletin of the American Physical Society"]},{"language":[{"iso":"eng"}],"publisher":"American Physical Society","date_published":"2020-03-01T00:00:00Z","month":"03","date_created":"2022-01-28T10:09:19Z","conference":{"location":"Denver, CO, United States","end_date":"2020-03-06","name":"APS: American Physical Society","start_date":"2020-03-02"},"status":"public","intvolume":"        65","type":"conference","day":"01","publication":"APS March Meeting 2020","issue":"1","title":"Correlated states and tunable topological bands in twisted monolayer-bilayer graphene heterostructures","year":"2020","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR20/Session/B51.5"}],"article_number":"B51.00005","alternative_title":["Bulletin of the American Physical Society"],"author":[{"first_name":"Hryhoriy","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"first_name":"Jihang","last_name":"Zhu","full_name":"Zhu, Jihang"},{"first_name":"Manish","last_name":"Kumar","full_name":"Kumar, Manish"},{"full_name":"Taniguchi, Takashi","last_name":"Taniguchi","first_name":"Takashi"},{"last_name":"Watanabe","full_name":"Watanabe, Kenji","first_name":"Kenji"},{"full_name":"MacDonald, Allan","last_name":"MacDonald","first_name":"Allan"},{"full_name":"Young, Andrea","last_name":"Young","first_name":"Andrea"}],"abstract":[{"lang":"eng","text":"We experimentally investigate twisted van der Waals heterostructures of monolayer graphene rotated with respect to a bernal stacked graphene bilayer. We report transport measurements for devices with twist angles between 0.9 and 1.4°. The electric field allows efficient tuning of the width, isolation and the topology of the moiré bands in this system. By comparing magnetoresistance measurements to numerical simulations, we develop an understanding of the band structure. Finally, we observe correlated states at half- and quarter-fillings, which arise when narrow moire sublattice band is isolated by energy gaps from dispersive bands. We investigate the effects of in-plane and out-of-plane magnetic field on these states and discuss the implication for their spin- and valley- polarization."}],"citation":{"chicago":"Polshyn, Hryhoriy, Jihang Zhu, Manish Kumar, Takashi Taniguchi, Kenji Watanabe, Allan MacDonald, and Andrea Young. “Correlated States and Tunable Topological Bands in Twisted Monolayer-Bilayer Graphene Heterostructures.” In <i>APS March Meeting 2020</i>, Vol. 65. American Physical Society, 2020.","ieee":"H. Polshyn <i>et al.</i>, “Correlated states and tunable topological bands in twisted monolayer-bilayer graphene heterostructures,” in <i>APS March Meeting 2020</i>, Denver, CO, United States, 2020, vol. 65, no. 1.","apa":"Polshyn, H., Zhu, J., Kumar, M., Taniguchi, T., Watanabe, K., MacDonald, A., &#38; Young, A. (2020). Correlated states and tunable topological bands in twisted monolayer-bilayer graphene heterostructures. In <i>APS March Meeting 2020</i> (Vol. 65). Denver, CO, United States: American Physical Society.","short":"H. Polshyn, J. Zhu, M. Kumar, T. Taniguchi, K. Watanabe, A. MacDonald, A. Young, in:, APS March Meeting 2020, American Physical Society, 2020.","ista":"Polshyn H, Zhu J, Kumar M, Taniguchi T, Watanabe K, MacDonald A, Young A. 2020. Correlated states and tunable topological bands in twisted monolayer-bilayer graphene heterostructures. APS March Meeting 2020. APS: American Physical Society, Bulletin of the American Physical Society, vol. 65, B51.00005.","ama":"Polshyn H, Zhu J, Kumar M, et al. Correlated states and tunable topological bands in twisted monolayer-bilayer graphene heterostructures. In: <i>APS March Meeting 2020</i>. Vol 65. American Physical Society; 2020.","mla":"Polshyn, Hryhoriy, et al. “Correlated States and Tunable Topological Bands in Twisted Monolayer-Bilayer Graphene Heterostructures.” <i>APS March Meeting 2020</i>, vol. 65, no. 1, B51.00005, American Physical Society, 2020."},"publication_status":"published","oa_version":"Published Version","quality_controlled":"1","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","publication_identifier":{"issn":["0003-0503"]},"extern":"1","_id":"10696","article_processing_charge":"No","oa":1,"date_updated":"2022-02-08T10:22:08Z","volume":65},{"title":"Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part I: Device fabrication and transport","external_id":{"arxiv":["1907.00261"]},"year":"2020","related_material":{"record":[{"status":"public","id":"10619","relation":"other"}]},"article_number":"B59.00012","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR20/Session/B59.12"}],"alternative_title":["Bulletin of the American Physical Society"],"author":[{"full_name":"Zhang, Yuxuan","last_name":"Zhang","first_name":"Yuxuan"},{"last_name":"Serlin","full_name":"Serlin, Marec","first_name":"Marec"},{"last_name":"Tschirhart","full_name":"Tschirhart, Charles","first_name":"Charles"},{"full_name":"Polshyn, Hryhoriy","last_name":"Polshyn","orcid":"0000-0001-8223-8896","first_name":"Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"last_name":"Zhu","full_name":"Zhu, Jiacheng","first_name":"Jiacheng"},{"full_name":"Balents, Leon","last_name":"Balents","first_name":"Leon"},{"last_name":"Huber","full_name":"Huber, Martin E.","first_name":"Martin E."},{"first_name":"Takashi","full_name":"Taniguchi, Takashi","last_name":"Taniguchi"},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"full_name":"Young, Andrea","last_name":"Young","first_name":"Andrea"}],"abstract":[{"text":"We report the observation of a quantized anomalous Hall effect in a moiré heterostructure consisting of twisted bilayer graphene aligned to an encapsulating hBN substrate. The effect occurs at a density of 3 electrons per superlattice unit cell, where we observe magnetic hysteresis and a Hall resistance quantized to within 0.1% of the resistance quantum at temperatures as high as 3K. In this first of 3 talks, I will describe the fabrication procedure for our device as well as basic transport characterization measurements. I will introduce the phenomenology of twisted bilayer graphene and present evidence for hBN alignment as manifested in the hierarchy of symmetry-breaking gaps and anomalous magnetoresistance.","lang":"eng"}],"citation":{"ama":"Zhang Y, Serlin M, Tschirhart C, et al. Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part I: Device fabrication and transport. In: <i>APS March Meeting 2020</i>. Vol 65. American Physical Society; 2020.","mla":"Zhang, Yuxuan, et al. “Intrinsic Quantized Anomalous Hall Effect in a Moiré Heterostructure, Part I: Device Fabrication and Transport.” <i>APS March Meeting 2020</i>, vol. 65, no. 1, B59.00012, American Physical Society, 2020.","ista":"Zhang Y, Serlin M, Tschirhart C, Polshyn H, Zhu J, Balents L, Huber ME, Taniguchi T, Watanabe K, Young A. 2020. Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part I: Device fabrication and transport. APS March Meeting 2020. APS: American Physical Society, Bulletin of the American Physical Society, vol. 65, B59.00012.","short":"Y. Zhang, M. Serlin, C. Tschirhart, H. Polshyn, J. Zhu, L. Balents, M.E. Huber, T. Taniguchi, K. Watanabe, A. Young, in:, APS March Meeting 2020, American Physical Society, 2020.","apa":"Zhang, Y., Serlin, M., Tschirhart, C., Polshyn, H., Zhu, J., Balents, L., … Young, A. (2020). Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part I: Device fabrication and transport. In <i>APS March Meeting 2020</i> (Vol. 65). Denver, CO, United States: American Physical Society.","ieee":"Y. Zhang <i>et al.</i>, “Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part I: Device fabrication and transport,” in <i>APS March Meeting 2020</i>, Denver, CO, United States, 2020, vol. 65, no. 1.","chicago":"Zhang, Yuxuan, Marec Serlin, Charles Tschirhart, Hryhoriy Polshyn, Jiacheng Zhu, Leon Balents, Martin E. Huber, Takashi Taniguchi, Kenji Watanabe, and Andrea Young. “Intrinsic Quantized Anomalous Hall Effect in a Moiré Heterostructure, Part I: Device Fabrication and Transport.” In <i>APS March Meeting 2020</i>, Vol. 65. American Physical Society, 2020."},"publication_status":"published","quality_controlled":"1","oa_version":"Published Version","acknowledgement":"I would like to thank the MURI program, Sloan foundation, AFOSR, and ARO for their generous support of this work.","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","extern":"1","_id":"10697","article_processing_charge":"No","oa":1,"date_updated":"2023-02-21T15:57:52Z","volume":65,"arxiv":1,"language":[{"iso":"eng"}],"publisher":"American Physical Society","date_published":"2020-03-01T00:00:00Z","month":"03","date_created":"2022-01-28T10:28:35Z","conference":{"start_date":"2020-03-02","location":"Denver, CO, United States","name":"APS: American Physical Society","end_date":"2020-03-06"},"status":"public","intvolume":"        65","type":"conference","day":"01","publication":"APS March Meeting 2020","issue":"1"},{"conference":{"end_date":"2020-03-06","location":"Denver, CO, United States","name":"APS: American Physical Society","start_date":"2020-03-02"},"date_created":"2022-01-28T10:46:57Z","month":"03","date_published":"2020-03-01T00:00:00Z","publisher":"American Physical Society","language":[{"iso":"eng"}],"publication":"APS March Meeting 2020","issue":"1","day":"01","type":"conference","intvolume":"        65","status":"public","alternative_title":["Bulletin of the American Physical Society"],"article_number":"B59.00011","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR20/Session/B59.11"}],"related_material":{"record":[{"status":"public","relation":"other","id":"10619"}]},"year":"2020","external_id":{"arxiv":["1907.00261"]},"title":"Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part II: Temperature dependence and current switching","arxiv":1,"article_processing_charge":"No","date_updated":"2023-02-21T15:57:52Z","oa":1,"volume":65,"extern":"1","_id":"10698","quality_controlled":"1","oa_version":"Published Version","acknowledgement":"I would like to thank the MURI Program, AFOSR, Sloan Foundation, and the ARO for their generous support of this work.","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","citation":{"chicago":"Serlin, Marec, Charles Tschirhart, Hryhoriy Polshyn, Yuxuan Zhang, Jiacheng Zhu, Martin E. Huber, Leon Balents, Kenji Watanabe, Takashi Tanaguchi, and Andrea Young. “Intrinsic Quantized Anomalous Hall Effect in a Moiré Heterostructure, Part II: Temperature Dependence and Current Switching.” In <i>APS March Meeting 2020</i>, Vol. 65. American Physical Society, 2020.","apa":"Serlin, M., Tschirhart, C., Polshyn, H., Zhang, Y., Zhu, J., Huber, M. E., … Young, A. (2020). Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part II: Temperature dependence and current switching. In <i>APS March Meeting 2020</i> (Vol. 65). Denver, CO, United States: American Physical Society.","ieee":"M. Serlin <i>et al.</i>, “Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part II: Temperature dependence and current switching,” in <i>APS March Meeting 2020</i>, Denver, CO, United States, 2020, vol. 65, no. 1.","ista":"Serlin M, Tschirhart C, Polshyn H, Zhang Y, Zhu J, Huber ME, Balents L, Watanabe K, Tanaguchi T, Young A. 2020. Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part II: Temperature dependence and current switching. APS March Meeting 2020. APS: American Physical Society, Bulletin of the American Physical Society, vol. 65, B59.00011.","short":"M. Serlin, C. Tschirhart, H. Polshyn, Y. Zhang, J. Zhu, M.E. Huber, L. Balents, K. Watanabe, T. Tanaguchi, A. Young, in:, APS March Meeting 2020, American Physical Society, 2020.","mla":"Serlin, Marec, et al. “Intrinsic Quantized Anomalous Hall Effect in a Moiré Heterostructure, Part II: Temperature Dependence and Current Switching.” <i>APS March Meeting 2020</i>, vol. 65, no. 1, B59.00011, American Physical Society, 2020.","ama":"Serlin M, Tschirhart C, Polshyn H, et al. Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part II: Temperature dependence and current switching. In: <i>APS March Meeting 2020</i>. Vol 65. American Physical Society; 2020."},"publication_status":"published","abstract":[{"lang":"eng","text":"This is the second of three talks describing the observation and characterization of a ferromagnetic moiré heterostructure based on twisted bilayer graphene aligned to hexagonal boron nitride. I will compare the qualitative and quantitative features of this observed quantum anomalous Hall state to traditional systems engineered from thin film (Bi,Sb)2Te3 topological insulators. In particular, we find that the measured electronic energy gap of ~30K is several times higher than the Curie temperature, consistent with a lack of disorder associated with magnetic dopants. In this system, the quantization arises from spontaneous ferromagnetic polarization into a single spin and valley moiré subband, which is topological despite the lack of spin orbit coupling. I will also discuss the observation of current induced switching, which allows the magnetic state of the heterostructure to be controllably reversed with currents as small as a few nanoamperes."}],"author":[{"last_name":"Serlin","full_name":"Serlin, Marec","first_name":"Marec"},{"last_name":"Tschirhart","full_name":"Tschirhart, Charles","first_name":"Charles"},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","first_name":"Hryhoriy"},{"first_name":"Yuxuan","last_name":"Zhang","full_name":"Zhang, Yuxuan"},{"first_name":"Jiacheng","full_name":"Zhu, Jiacheng","last_name":"Zhu"},{"last_name":"Huber","full_name":"Huber, Martin E.","first_name":"Martin E."},{"last_name":"Balents","full_name":"Balents, Leon","first_name":"Leon"},{"first_name":"Kenji","last_name":"Watanabe","full_name":"Watanabe, Kenji"},{"first_name":"Takashi","full_name":"Tanaguchi, Takashi","last_name":"Tanaguchi"},{"last_name":"Young","full_name":"Young, Andrea","first_name":"Andrea"}]},{"year":"2020","external_id":{"arxiv":["1907.00261"]},"title":"Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part III: Scanning probe magnetometry","alternative_title":["Bulletin of the American Physical Society"],"article_number":"B59.00013","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR20/Session/B59.13"}],"related_material":{"record":[{"status":"public","id":"10619","relation":"other"}]},"publication_status":"published","citation":{"chicago":"Tschirhart, Charles, Marec Serlin, Hryhoriy Polshyn, Yuxuan Zhang, Jiacheng Zhu, Leon Balents, Martin E. Huber, Kenji Watanabe, Takashi Tanaguchi, and Andrea Young. “Intrinsic Quantized Anomalous Hall Effect in a Moiré Heterostructure, Part III: Scanning Probe Magnetometry.” In <i>APS March Meeting 2020</i>, Vol. 65. American Physical Society, 2020.","apa":"Tschirhart, C., Serlin, M., Polshyn, H., Zhang, Y., Zhu, J., Balents, L., … Young, A. (2020). Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part III: Scanning probe magnetometry. In <i>APS March Meeting 2020</i> (Vol. 65). Denver, CO, United States: American Physical Society.","ieee":"C. Tschirhart <i>et al.</i>, “Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part III: Scanning probe magnetometry,” in <i>APS March Meeting 2020</i>, Denver, CO, United States, 2020, vol. 65, no. 1.","ista":"Tschirhart C, Serlin M, Polshyn H, Zhang Y, Zhu J, Balents L, Huber ME, Watanabe K, Tanaguchi T, Young A. 2020. Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part III: Scanning probe magnetometry. APS March Meeting 2020. APS: American Physical Society, Bulletin of the American Physical Society, vol. 65, B59.00013.","short":"C. Tschirhart, M. Serlin, H. Polshyn, Y. Zhang, J. Zhu, L. Balents, M.E. Huber, K. Watanabe, T. Tanaguchi, A. Young, in:, APS March Meeting 2020, American Physical Society, 2020.","mla":"Tschirhart, Charles, et al. “Intrinsic Quantized Anomalous Hall Effect in a Moiré Heterostructure, Part III: Scanning Probe Magnetometry.” <i>APS March Meeting 2020</i>, vol. 65, no. 1, B59.00013, American Physical Society, 2020.","ama":"Tschirhart C, Serlin M, Polshyn H, et al. Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part III: Scanning probe magnetometry. In: <i>APS March Meeting 2020</i>. Vol 65. American Physical Society; 2020."},"abstract":[{"lang":"eng","text":"This is the third of three talks describing the observation and characterization of a ferromagnetic moiré heterostructure based on twisted bilayer graphene aligned to hexagonal boron nitride. In this segment I will present scanning probe magnetometry data acquired using a nanoSQUID-on-tip microscope, which provides ~150 nm spatial resolution and a field sensitivity of ~10 nT/rtHz. We study the distribution of magnetic domains within the device as a function of density, magnetic field training, and DC current. Our data allow us to constrain the magnitude of the orbital magnetic moment of the electrons in the QAH state. Comparison with simultaneously acquired transport data allows us to precisely correlate single domain dynamics with discrete jumps in the observed anomalous Hall signal."}],"author":[{"first_name":"Charles","full_name":"Tschirhart, Charles","last_name":"Tschirhart"},{"first_name":"Marec","full_name":"Serlin, Marec","last_name":"Serlin"},{"orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn","first_name":"Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"last_name":"Zhang","full_name":"Zhang, Yuxuan","first_name":"Yuxuan"},{"last_name":"Zhu","full_name":"Zhu, Jiacheng","first_name":"Jiacheng"},{"first_name":"Leon","last_name":"Balents","full_name":"Balents, Leon"},{"first_name":"Martin E.","last_name":"Huber","full_name":"Huber, Martin E."},{"first_name":"Kenji","last_name":"Watanabe","full_name":"Watanabe, Kenji"},{"last_name":"Tanaguchi","full_name":"Tanaguchi, Takashi","first_name":"Takashi"},{"first_name":"Andrea","full_name":"Young, Andrea","last_name":"Young"}],"arxiv":1,"volume":65,"oa":1,"date_updated":"2023-02-21T15:57:52Z","article_processing_charge":"No","_id":"10699","publication_identifier":{"issn":["0003-0503"]},"extern":"1","acknowledgement":"I would like to thank the MURI program, Sloan foundation, AFOSR, and ARO for their generous support of this work. I would also like to thank the NSF GRFP and the Hertz foundation for their generous support of my graduate studies.","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","oa_version":"Published Version","quality_controlled":"1","month":"03","date_published":"2020-03-01T00:00:00Z","publisher":"American Physical Society","language":[{"iso":"eng"}],"conference":{"end_date":"2020-03-06","name":"APS: American Physical Society","location":"Denver, CO, United States","start_date":"2020-03-02"},"date_created":"2022-01-28T10:57:49Z","day":"01","type":"conference","intvolume":"        65","status":"public","issue":"1","publication":"APS March Meeting 2020"},{"language":[{"iso":"eng"}],"publisher":"Springer Nature","date_published":"2020-02-01T00:00:00Z","article_type":"original","month":"02","date_created":"2022-01-28T12:04:09Z","status":"public","intvolume":"        16","type":"journal_article","day":"01","page":"154-158","issue":"2","publication":"Nature Physics","title":"Skyrmion solids in monolayer graphene","external_id":{"arxiv":["1904.11485"]},"year":"2020","doi":"10.1038/s41567-019-0729-8","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/1904.11485"}],"author":[{"first_name":"Haoxin","full_name":"Zhou, Haoxin","last_name":"Zhou"},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","first_name":"Hryhoriy","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn"},{"last_name":"Taniguchi","full_name":"Taniguchi, Takashi","first_name":"Takashi"},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"first_name":"Andrea F.","full_name":"Young, Andrea F.","last_name":"Young"}],"abstract":[{"text":"Partially filled Landau levels host competing electronic orders. For example, electron solids may prevail close to integer filling of the Landau levels before giving way to fractional quantum Hall liquids at higher carrier density1,2. Here, we report the observation of an electron solid with non-collinear spin texture in monolayer graphene, consistent with solidification of skyrmions3—topological spin textures characterized by quantized electrical charge4,5. We probe the spin texture of the solids using a modified Corbino geometry that allows ferromagnetic magnons to be launched and detected6,7. We find that magnon transport is highly efficient when one Landau level is filled (ν=1), consistent with quantum Hall ferromagnetic spin polarization. However, even minimal doping immediately quenches the magnon signal while leaving the vanishing low-temperature charge conductivity unchanged. Our results can be understood by the formation of a solid of charged skyrmions near ν=1, whose non-collinear spin texture leads to rapid magnon decay. Data near fractional fillings show evidence of several fractional skyrmion solids, suggesting that graphene hosts a highly tunable landscape of coupled spin and charge orders.","lang":"eng"}],"publication_status":"published","citation":{"chicago":"Zhou, Haoxin, Hryhoriy Polshyn, Takashi Taniguchi, Kenji Watanabe, and Andrea F. Young. “Skyrmion Solids in Monolayer Graphene.” <i>Nature Physics</i>. Springer Nature, 2020. <a href=\"https://doi.org/10.1038/s41567-019-0729-8\">https://doi.org/10.1038/s41567-019-0729-8</a>.","apa":"Zhou, H., Polshyn, H., Taniguchi, T., Watanabe, K., &#38; Young, A. F. (2020). Skyrmion solids in monolayer graphene. <i>Nature Physics</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41567-019-0729-8\">https://doi.org/10.1038/s41567-019-0729-8</a>","ieee":"H. Zhou, H. Polshyn, T. Taniguchi, K. Watanabe, and A. F. Young, “Skyrmion solids in monolayer graphene,” <i>Nature Physics</i>, vol. 16, no. 2. Springer Nature, pp. 154–158, 2020.","short":"H. Zhou, H. Polshyn, T. Taniguchi, K. Watanabe, A.F. Young, Nature Physics 16 (2020) 154–158.","ista":"Zhou H, Polshyn H, Taniguchi T, Watanabe K, Young AF. 2020. Skyrmion solids in monolayer graphene. Nature Physics. 16(2), 154–158.","ama":"Zhou H, Polshyn H, Taniguchi T, Watanabe K, Young AF. Skyrmion solids in monolayer graphene. <i>Nature Physics</i>. 2020;16(2):154-158. doi:<a href=\"https://doi.org/10.1038/s41567-019-0729-8\">10.1038/s41567-019-0729-8</a>","mla":"Zhou, Haoxin, et al. “Skyrmion Solids in Monolayer Graphene.” <i>Nature Physics</i>, vol. 16, no. 2, Springer Nature, 2020, pp. 154–58, doi:<a href=\"https://doi.org/10.1038/s41567-019-0729-8\">10.1038/s41567-019-0729-8</a>."},"acknowledgement":"We acknowledge discussions with B. Halperin, C. Huang, A. Macdonald and M. Zalatel. Experimental work at UCSB was supported by the Army Research Office under awards nos. MURI W911NF-16-1-0361 and W911NF-16-1-0482. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by MEXT (Japan) and CREST (JPMJCR15F3), JST. A.F.Y. acknowledges the support of the David and Lucile Packard Foundation and and Alfred. P. Sloan Foundation.","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","oa_version":"Preprint","quality_controlled":"1","_id":"10701","extern":"1","publication_identifier":{"issn":["1745-2473"],"eissn":["1745-2481"]},"volume":16,"date_updated":"2022-01-31T07:10:07Z","oa":1,"article_processing_charge":"No","arxiv":1},{"year":"2020","doi":"10.1038/s41586-020-2963-8","title":"Electrical switching of magnetic order in an orbital Chern insulator","external_id":{"pmid":["33230333"],"arxiv":["2004.11353"]},"main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2004.11353"}],"publication_status":"published","citation":{"chicago":"Polshyn, Hryhoriy, J. Zhu, M. A. Kumar, Y. Zhang, F. Yang, C. L. Tschirhart, M. Serlin, et al. “Electrical Switching of Magnetic Order in an Orbital Chern Insulator.” <i>Nature</i>. Springer Nature, 2020. <a href=\"https://doi.org/10.1038/s41586-020-2963-8\">https://doi.org/10.1038/s41586-020-2963-8</a>.","apa":"Polshyn, H., Zhu, J., Kumar, M. A., Zhang, Y., Yang, F., Tschirhart, C. L., … Young, A. F. (2020). Electrical switching of magnetic order in an orbital Chern insulator. <i>Nature</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41586-020-2963-8\">https://doi.org/10.1038/s41586-020-2963-8</a>","ieee":"H. Polshyn <i>et al.</i>, “Electrical switching of magnetic order in an orbital Chern insulator,” <i>Nature</i>, vol. 588, no. 7836. Springer Nature, pp. 66–70, 2020.","short":"H. Polshyn, J. Zhu, M.A. Kumar, Y. Zhang, F. Yang, C.L. Tschirhart, M. Serlin, K. Watanabe, T. Taniguchi, A.H. MacDonald, A.F. Young, Nature 588 (2020) 66–70.","ista":"Polshyn H, Zhu J, Kumar MA, Zhang Y, Yang F, Tschirhart CL, Serlin M, Watanabe K, Taniguchi T, MacDonald AH, Young AF. 2020. Electrical switching of magnetic order in an orbital Chern insulator. Nature. 588(7836), 66–70.","ama":"Polshyn H, Zhu J, Kumar MA, et al. Electrical switching of magnetic order in an orbital Chern insulator. <i>Nature</i>. 2020;588(7836):66-70. doi:<a href=\"https://doi.org/10.1038/s41586-020-2963-8\">10.1038/s41586-020-2963-8</a>","mla":"Polshyn, Hryhoriy, et al. “Electrical Switching of Magnetic Order in an Orbital Chern Insulator.” <i>Nature</i>, vol. 588, no. 7836, Springer Nature, 2020, pp. 66–70, doi:<a href=\"https://doi.org/10.1038/s41586-020-2963-8\">10.1038/s41586-020-2963-8</a>."},"abstract":[{"lang":"eng","text":"Magnetism typically arises from the joint effect of Fermi statistics and repulsive Coulomb interactions, which favours ground states with non-zero electron spin. As a result, controlling spin magnetism with electric fields—a longstanding technological goal in spintronics and multiferroics1,2—can be achieved only indirectly. Here we experimentally demonstrate direct electric-field control of magnetic states in an orbital Chern insulator3,4,5,6, a magnetic system in which non-trivial band topology favours long-range order of orbital angular momentum but the spins are thought to remain disordered7,8,9,10,11,12,13,14. We use van der Waals heterostructures consisting of a graphene monolayer rotationally faulted with respect to a Bernal-stacked bilayer to realize narrow and topologically non-trivial valley-projected moiré minibands15,16,17. At fillings of one and three electrons per moiré unit cell within these bands, we observe quantized anomalous Hall effects18 with transverse resistance approximately equal to h/2e2 (where h is Planck’s constant and e is the charge on the electron), which is indicative of spontaneous polarization of the system into a single-valley-projected band with a Chern number equal to two. At a filling of three electrons per moiré unit cell, we find that the sign of the quantum anomalous Hall effect can be reversed via field-effect control of the chemical potential; moreover, this transition is hysteretic, which we use to demonstrate non-volatile electric-field-induced reversal of the magnetic state. A theoretical analysis19 indicates that the effect arises from the topological edge states, which drive a change in sign of the magnetization and thus a reversal in the favoured magnetic state. Voltage control of magnetic states can be used to electrically pattern non-volatile magnetic-domain structures hosting chiral edge states, with applications ranging from reconfigurable microwave circuit elements to ultralow-power magnetic memories."}],"author":[{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn","orcid":"0000-0001-8223-8896"},{"first_name":"J.","last_name":"Zhu","full_name":"Zhu, J."},{"full_name":"Kumar, M. A.","last_name":"Kumar","first_name":"M. A."},{"full_name":"Zhang, Y.","last_name":"Zhang","first_name":"Y."},{"first_name":"F.","last_name":"Yang","full_name":"Yang, F."},{"first_name":"C. L.","full_name":"Tschirhart, C. L.","last_name":"Tschirhart"},{"full_name":"Serlin, M.","last_name":"Serlin","first_name":"M."},{"first_name":"K.","last_name":"Watanabe","full_name":"Watanabe, K."},{"last_name":"Taniguchi","full_name":"Taniguchi, T.","first_name":"T."},{"full_name":"MacDonald, A. H.","last_name":"MacDonald","first_name":"A. H."},{"first_name":"A. F.","full_name":"Young, A. F.","last_name":"Young"}],"keyword":["multidisciplinary"],"arxiv":1,"date_updated":"2022-01-13T14:21:04Z","volume":588,"oa":1,"article_processing_charge":"No","pmid":1,"_id":"10618","extern":"1","publication_identifier":{"eissn":["1476-4687"],"issn":["0028-0836"]},"acknowledgement":"We acknowledge discussions with J. Checkelsky, S. Chen, C. Dean, M. Yankowitz, D. Reilly, I. Sodemann and M. Zaletel. Work at UCSB was primarily supported by the ARO under MURI W911NF-16-1-0361. Measurements of twisted bilayer graphene (Extended Data Fig. 8) and measurements at elevated temperatures (Extended Data Fig. 3) were supported by a SEED grant and made use of shared facilities of the UCSB MRSEC (NSF DMR 1720256), a member of the Materials Research Facilities Network (www.mrfn.org). A.F.Y. acknowledges the support of the David and Lucille Packard Foundation under award 2016-65145. A.H.M. and J.Z. were supported by the National Science Foundation through the Center for Dynamics and Control of Materials, an NSF MRSEC under Cooperative Agreement number DMR-1720595, and by the Welch Foundation under grant TBF1473. C.L.T. acknowledges support from the Hertz Foundation and from the National Science Foundation Graduate Research Fellowship Program under grant 1650114. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan, Grant Number JPMXP0112101001, JSPS KAKENHI grant numbers JP20H00354 and the CREST(JPMJCR15F3), JST.","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","oa_version":"Preprint","quality_controlled":"1","month":"11","date_published":"2020-11-23T00:00:00Z","article_type":"original","publisher":"Springer Nature","scopus_import":"1","language":[{"iso":"eng"}],"date_created":"2022-01-13T14:12:17Z","day":"23","type":"journal_article","intvolume":"       588","status":"public","issue":"7836","publication":"Nature","page":"66-70"},{"date_updated":"2022-01-24T08:05:51Z","oa":1,"page":"55","article_processing_charge":"No","arxiv":1,"publication":"arXiv","acknowledgement":"We thank NSF CMP program for suggestions regarding the topic and general structure of the workshop. This project was supported by the NSF DMR-2002329 and The Gordon and Betty Moore Foundation (GBMF) EPiQS initiative. We would like to sincerely thank A. Kapitulnik, A. J. Leggett, M.B. Maple, T.M. McQueen, M. Norman, P. S. Riseborough, and G. A. Sawatzky for their lectures at the workshop and advice on the writing of this manuscript. We would also like to thank G. Blumberg, C. Broholm, S. Crooker, N. Drichko, and A. Patel for helpful consultation on topics discussed\r\nherein. A number of individuals also had independent support: (AA, EH; GBMF-4305), (IMH; GBMF-9071), (HJC; NHMFL is supported by the NSF DMR-1644779 and the state of Florida), (YH, AZ; Miller Institute for Basic Research in Science), (YC; US DOE-BES DEAC02-06CH11357), (AS; Spallation Neutron Source, a DOE Office of Science User Facility operated by ORNL), (SAAG; ARO-W911NF-18-1-0290, NSF DMR-1455233), (YW; DOE-BES DE-SC0019331, GBMF-4532).","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","oa_version":"Preprint","_id":"10650","extern":"1","type":"preprint","publication_status":"submitted","day":"01","citation":{"mla":"Alexandradinata, A., et al. “The Future of the Correlated Electron Problem.” <i>ArXiv</i>.","ama":"Alexandradinata A, Armitage NP, Baydin A, et al. The future of the correlated electron problem. <i>arXiv</i>.","ista":"Alexandradinata A, Armitage NP, Baydin A, Bi W, Cao Y, Changlani HJ, Chertkov E, da Silva Neto EH, Delacretaz L, El Baggari I, Ferguson GM, Gannon WJ, Ghorashi SAA, Goodge BH, Goulko O, Grissonnache G, Hallas A, Hayes IM, He Y, Huang EW, Kogar A, Kumah D, Lee JY, Legros A, Mahmood F, Maximenko Y, Pellatz N, Polshyn H, Sarkar T, Scheie A, Seyler KL, Shi Z, Skinner B, Steinke L, Thirunavukkuarasu K, Trevisan TV, Vogl M, Volkov PA, Wang Y, Wang Y, Wei D, Wei K, Yang S, Zhang X, Zhang Y-H, Zhao L, Zong A. The future of the correlated electron problem. arXiv, .","short":"A. Alexandradinata, N.P. Armitage, A. Baydin, W. Bi, Y. Cao, H.J. Changlani, E. Chertkov, E.H. da Silva Neto, L. Delacretaz, I. El Baggari, G.M. Ferguson, W.J. Gannon, S.A.A. Ghorashi, B.H. Goodge, O. Goulko, G. Grissonnache, A. Hallas, I.M. Hayes, Y. He, E.W. Huang, A. Kogar, D. Kumah, J.Y. Lee, A. Legros, F. Mahmood, Y. Maximenko, N. Pellatz, H. Polshyn, T. Sarkar, A. Scheie, K.L. Seyler, Z. Shi, B. Skinner, L. Steinke, K. Thirunavukkuarasu, T.V. Trevisan, M. Vogl, P.A. Volkov, Y. Wang, Y. Wang, D. Wei, K. Wei, S. Yang, X. Zhang, Y.-H. Zhang, L. Zhao, A. Zong, ArXiv (n.d.).","apa":"Alexandradinata, A., Armitage, N. P., Baydin, A., Bi, W., Cao, Y., Changlani, H. J., … Zong, A. (n.d.). The future of the correlated electron problem. <i>arXiv</i>.","ieee":"A. Alexandradinata <i>et al.</i>, “The future of the correlated electron problem,” <i>arXiv</i>. .","chicago":"Alexandradinata, A, N.P. Armitage, Andrey Baydin, Wenli Bi, Yue Cao, Hitesh J. Changlani, Eli Chertkov, et al. “The Future of the Correlated Electron Problem.” <i>ArXiv</i>, n.d."},"status":"public","author":[{"first_name":"A","last_name":"Alexandradinata","full_name":"Alexandradinata, A"},{"full_name":"Armitage, N.P.","last_name":"Armitage","first_name":"N.P."},{"full_name":"Baydin, Andrey","last_name":"Baydin","first_name":"Andrey"},{"first_name":"Wenli","last_name":"Bi","full_name":"Bi, Wenli"},{"first_name":"Yue","last_name":"Cao","full_name":"Cao, Yue"},{"last_name":"Changlani","full_name":"Changlani, Hitesh J.","first_name":"Hitesh J."},{"full_name":"Chertkov, Eli","last_name":"Chertkov","first_name":"Eli"},{"last_name":"da Silva Neto","full_name":"da Silva Neto, Eduardo H.","first_name":"Eduardo H."},{"first_name":"Luca","last_name":"Delacretaz","full_name":"Delacretaz, Luca"},{"first_name":"Ismail","full_name":"El Baggari, Ismail","last_name":"El Baggari"},{"last_name":"Ferguson","full_name":"Ferguson, G.M.","first_name":"G.M."},{"full_name":"Gannon, William J.","last_name":"Gannon","first_name":"William J."},{"first_name":"Sayed Ali Akbar","last_name":"Ghorashi","full_name":"Ghorashi, Sayed Ali Akbar"},{"first_name":"Berit H.","last_name":"Goodge","full_name":"Goodge, Berit H."},{"last_name":"Goulko","full_name":"Goulko, Olga","first_name":"Olga"},{"last_name":"Grissonnache","full_name":"Grissonnache, G.","first_name":"G."},{"last_name":"Hallas","full_name":"Hallas, Alannah","first_name":"Alannah"},{"full_name":"Hayes, Ian M.","last_name":"Hayes","first_name":"Ian M."},{"last_name":"He","full_name":"He, Yu","first_name":"Yu"},{"full_name":"Huang, Edwin W.","last_name":"Huang","first_name":"Edwin W."},{"full_name":"Kogar, Anshu","last_name":"Kogar","first_name":"Anshu"},{"last_name":"Kumah","full_name":"Kumah, Divine","first_name":"Divine"},{"first_name":"Jong Yeon","last_name":"Lee","full_name":"Lee, Jong Yeon"},{"last_name":"Legros","full_name":"Legros, A.","first_name":"A."},{"last_name":"Mahmood","full_name":"Mahmood, Fahad","first_name":"Fahad"},{"full_name":"Maximenko, Yulia","last_name":"Maximenko","first_name":"Yulia"},{"last_name":"Pellatz","full_name":"Pellatz, Nick","first_name":"Nick"},{"first_name":"Hryhoriy","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"first_name":"Tarapada","full_name":"Sarkar, Tarapada","last_name":"Sarkar"},{"first_name":"Allen","full_name":"Scheie, Allen","last_name":"Scheie"},{"last_name":"Seyler","full_name":"Seyler, Kyle L.","first_name":"Kyle L."},{"full_name":"Shi, Zhenzhong","last_name":"Shi","first_name":"Zhenzhong"},{"first_name":"Brian","last_name":"Skinner","full_name":"Skinner, Brian"},{"last_name":"Steinke","full_name":"Steinke, Lucia","first_name":"Lucia"},{"first_name":"K.","last_name":"Thirunavukkuarasu","full_name":"Thirunavukkuarasu, K."},{"first_name":"Thaís Victa","last_name":"Trevisan","full_name":"Trevisan, Thaís Victa"},{"full_name":"Vogl, Michael","last_name":"Vogl","first_name":"Michael"},{"first_name":"Pavel A.","full_name":"Volkov, Pavel A.","last_name":"Volkov"},{"first_name":"Yao","last_name":"Wang","full_name":"Wang, Yao"},{"full_name":"Wang, Yishu","last_name":"Wang","first_name":"Yishu"},{"full_name":"Wei, Di","last_name":"Wei","first_name":"Di"},{"first_name":"Kaya","last_name":"Wei","full_name":"Wei, Kaya"},{"last_name":"Yang","full_name":"Yang, Shuolong","first_name":"Shuolong"},{"full_name":"Zhang, Xian","last_name":"Zhang","first_name":"Xian"},{"last_name":"Zhang","full_name":"Zhang, Ya-Hui","first_name":"Ya-Hui"},{"full_name":"Zhao, Liuyan","last_name":"Zhao","first_name":"Liuyan"},{"last_name":"Zong","full_name":"Zong, Alfred","first_name":"Alfred"}],"abstract":[{"text":"The understanding of material systems with strong electron-electron interactions is the central problem in modern condensed matter physics. Despite this, the essential physics of many of these materials is still not understood and we have no overall perspective on their properties. Moreover, we have very little ability to make predictions in this class of systems. In this manuscript we share our personal views of what the major open problems are in correlated electron systems and we discuss some possible routes to make progress in this rich and fascinating field. This manuscript is the result of the vigorous discussions and deliberations that took place at Johns Hopkins University during a three-day workshop January 27, 28, and 29, 2020 that brought together six senior scientists and 46 more junior scientists. Our hope, is that the topics we have presented will provide inspiration for others working in this field and motivation for the idea that significant progress can be made on very hard problems if we focus our collective energies.","lang":"eng"}],"main_file_link":[{"url":"https://arxiv.org/abs/2010.00584","open_access":"1"}],"date_created":"2022-01-20T10:55:36Z","date_published":"2020-10-01T00:00:00Z","year":"2020","month":"10","language":[{"iso":"eng"}],"external_id":{"arxiv":["2010.00584"]},"title":"The future of the correlated electron problem"},{"month":"02","doi":"10.36471/jccm_february_2019_03","year":"2019","article_type":"original","date_published":"2019-02-28T00:00:00Z","title":"New correlated phenomena in magic-angle twisted bilayer graphene/s","publisher":"Simons Foundation ; University of California, Riverside","language":[{"iso":"eng"}],"main_file_link":[{"url":"https://www.condmatjclub.org/?p=3541","open_access":"1"}],"date_created":"2022-01-25T15:09:58Z","citation":{"mla":"Yankowitz, Mathew, et al. “New Correlated Phenomena in Magic-Angle Twisted Bilayer Graphene/S.” <i>Journal Club for Condensed Matter Physics</i>, vol. 03, Simons Foundation ; University of California, Riverside, 2019, doi:<a href=\"https://doi.org/10.36471/jccm_february_2019_03\">10.36471/jccm_february_2019_03</a>.","ama":"Yankowitz M, Chen S, Polshyn H, et al. New correlated phenomena in magic-angle twisted bilayer graphene/s. <i>Journal Club for Condensed Matter Physics</i>. 2019;03. doi:<a href=\"https://doi.org/10.36471/jccm_february_2019_03\">10.36471/jccm_february_2019_03</a>","short":"M. Yankowitz, S. Chen, H. Polshyn, K. Watanabe, T. Taniguchi, D. Graf, A.F. Young, C.R. Dean, A.L. Sharpe, E.J. Fox, A.W. Barnard, J. Finney, Journal Club for Condensed Matter Physics 03 (2019).","ista":"Yankowitz M, Chen S, Polshyn H, Watanabe K, Taniguchi T, Graf D, Young AF, Dean CR, Sharpe AL, Fox EJ, Barnard AW, Finney J. 2019. New correlated phenomena in magic-angle twisted bilayer graphene/s. Journal Club for Condensed Matter Physics. 03.","ieee":"M. Yankowitz <i>et al.</i>, “New correlated phenomena in magic-angle twisted bilayer graphene/s,” <i>Journal Club for Condensed Matter Physics</i>, vol. 03. Simons Foundation ; University of California, Riverside, 2019.","apa":"Yankowitz, M., Chen, S., Polshyn, H., Watanabe, K., Taniguchi, T., Graf, D., … Finney, J. (2019). New correlated phenomena in magic-angle twisted bilayer graphene/s. <i>Journal Club for Condensed Matter Physics</i>. Simons Foundation ; University of California, Riverside. <a href=\"https://doi.org/10.36471/jccm_february_2019_03\">https://doi.org/10.36471/jccm_february_2019_03</a>","chicago":"Yankowitz, Mathew, Shaowen Chen, Hryhoriy Polshyn, K. Watanabe, T. Taniguchi, David Graf, Andrea F. Young, et al. “New Correlated Phenomena in Magic-Angle Twisted Bilayer Graphene/S.” <i>Journal Club for Condensed Matter Physics</i>. Simons Foundation ; University of California, Riverside, 2019. <a href=\"https://doi.org/10.36471/jccm_february_2019_03\">https://doi.org/10.36471/jccm_february_2019_03</a>."},"day":"28","publication_status":"published","type":"journal_article","abstract":[{"text":"Since the discovery of correlated insulators and superconductivity in magic-angle twisted bilayer graphene (tBLG) ([1, 2], JCCM April 2018), theorists have been excitedly pursuing the alluring mix of band topology, symmetry breaking, Mott insulators and superconductivity at play, as well as the potential relation (if any) to high-Tc physics. Now a new stream\r\nof experimental work is arriving which further enriches the story. To briefly recap Episodes 1 and 2 (JCCM April and November 2018), when two graphene layers are stacked with a small rotational mismatch θ, the resulting long-wavelength moire pattern leads to a superlattice potential which reconstructs the low energy band structure. When θ approaches the “magic-angle” θM ∼ 1 ◦, the band structure features eight nearly-flat bands which fill when the electron number per moire unit cell, n/n0, lies between −4 < n/n0 < 4. The bands can be counted as 8 = 2 × 2 × 2: for each spin (2×) and valley (2×) characteristic of monolayergraphene, tBLG has has 2× flat bands which cross at mini-Dirac points.","lang":"eng"}],"intvolume":"         3","author":[{"full_name":"Yankowitz, Mathew","last_name":"Yankowitz","first_name":"Mathew"},{"first_name":"Shaowen","last_name":"Chen","full_name":"Chen, Shaowen"},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn","orcid":"0000-0001-8223-8896"},{"last_name":"Watanabe","full_name":"Watanabe, K.","first_name":"K."},{"full_name":"Taniguchi, T.","last_name":"Taniguchi","first_name":"T."},{"last_name":"Graf","full_name":"Graf, David","first_name":"David"},{"first_name":"Andrea F.","last_name":"Young","full_name":"Young, Andrea F."},{"full_name":"Dean, Cory R.","last_name":"Dean","first_name":"Cory R."},{"first_name":"Aaron L.","full_name":"Sharpe, Aaron L.","last_name":"Sharpe"},{"first_name":"E.J.","last_name":"Fox","full_name":"Fox, E.J."},{"first_name":"A.W.","full_name":"Barnard, A.W.","last_name":"Barnard"},{"last_name":"Finney","full_name":"Finney, Joe","first_name":"Joe"}],"status":"public","publication":"Journal Club for Condensed Matter Physics","article_processing_charge":"No","oa":1,"volume":"03","date_updated":"2022-01-25T15:56:39Z","_id":"10664","quality_controlled":"1","oa_version":"Published Version","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9"},{"date_published":"2019-03-01T00:00:00Z","month":"03","language":[{"iso":"eng"}],"publisher":"American Physical Society","date_created":"2022-02-04T11:54:21Z","conference":{"start_date":"2019-03-04","location":"Boston, MA, United States","end_date":"2019-03-08","name":"APS: American Physical Society"},"type":"conference","day":"01","status":"public","intvolume":"        64","issue":"2","publication":"APS March Meeting 2019","year":"2019","title":"Direct Imaging of magnetic structure in twisted bilayer graphene with scanning nanoSQUID-On-Tip microscopy","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR19/Session/L14.6"}],"article_number":"L14.00006","alternative_title":["Bulletin of the American Physical Society"],"publication_status":"published","citation":{"ieee":"M. Serlin, C. Tschirhart, H. Polshyn, J. Zhu, M. E. Huber, and A. Young, “Direct Imaging of magnetic structure in twisted bilayer graphene with scanning nanoSQUID-On-Tip microscopy,” in <i>APS March Meeting 2019</i>, Boston, MA, United States, 2019, vol. 64, no. 2.","apa":"Serlin, M., Tschirhart, C., Polshyn, H., Zhu, J., Huber, M. E., &#38; Young, A. (2019). Direct Imaging of magnetic structure in twisted bilayer graphene with scanning nanoSQUID-On-Tip microscopy. In <i>APS March Meeting 2019</i> (Vol. 64). Boston, MA, United States: American Physical Society.","chicago":"Serlin, Marec, Charles Tschirhart, Hryhoriy Polshyn, Jiacheng Zhu, Martin E. Huber, and Andrea Young. “Direct Imaging of Magnetic Structure in Twisted Bilayer Graphene with Scanning NanoSQUID-On-Tip Microscopy.” In <i>APS March Meeting 2019</i>, Vol. 64. American Physical Society, 2019.","mla":"Serlin, Marec, et al. “Direct Imaging of Magnetic Structure in Twisted Bilayer Graphene with Scanning NanoSQUID-On-Tip Microscopy.” <i>APS March Meeting 2019</i>, vol. 64, no. 2, L14.00006, American Physical Society, 2019.","ama":"Serlin M, Tschirhart C, Polshyn H, Zhu J, Huber ME, Young A. Direct Imaging of magnetic structure in twisted bilayer graphene with scanning nanoSQUID-On-Tip microscopy. In: <i>APS March Meeting 2019</i>. Vol 64. American Physical Society; 2019.","ista":"Serlin M, Tschirhart C, Polshyn H, Zhu J, Huber ME, Young A. 2019. Direct Imaging of magnetic structure in twisted bilayer graphene with scanning nanoSQUID-On-Tip microscopy. APS March Meeting 2019. APS: American Physical Society, Bulletin of the American Physical Society, vol. 64, L14.00006.","short":"M. Serlin, C. Tschirhart, H. Polshyn, J. Zhu, M.E. Huber, A. Young, in:, APS March Meeting 2019, American Physical Society, 2019."},"author":[{"first_name":"Marec","last_name":"Serlin","full_name":"Serlin, Marec"},{"first_name":"Charles","last_name":"Tschirhart","full_name":"Tschirhart, Charles"},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","first_name":"Hryhoriy","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn"},{"first_name":"Jiacheng","full_name":"Zhu, Jiacheng","last_name":"Zhu"},{"full_name":"Huber, Martin E.","last_name":"Huber","first_name":"Martin E."},{"last_name":"Young","full_name":"Young, Andrea","first_name":"Andrea"}],"abstract":[{"text":"Bilayer graphene, rotationally faulted to ~1.1 degree misalignment, has recently been shown to host superconducting and resistive states associated with the formation of a flat electronic band. While numerous theories exist for the origins of both states, direct validation of these theories remains an outstanding experimental problem. Here, we focus on the resistive states occurring at commensurate filling (1/2, 1/4, and 3/4) of the two lowest superlattice bands. We test theoretical proposals that these states arise due to broken spin—and/or valley—symmetry by performing direct magnetic imaging with nanoscale SQUID-on-tip microscopy. This technique provides single-spin resolved magnetometry on sub-100nm length scales. I will present imaging data from our 4.2K nSOT microscope on graphite-gated twisted bilayers near the flat band condition and discuss the implications for the physics of the commensurate resistive states.","lang":"eng"}],"volume":64,"oa":1,"date_updated":"2022-02-08T10:25:30Z","article_processing_charge":"No","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","quality_controlled":"1","oa_version":"Published Version","_id":"10722","publication_identifier":{"issn":["0003-0503"]},"extern":"1"},{"main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR19/Session/P01.4","open_access":"1"}],"article_number":"P01.00004","conference":{"name":"APS: American Physical Society","end_date":"2019-03-08","location":"Boston, MA, United States","start_date":"2019-03-04"},"date_created":"2022-02-04T12:14:02Z","month":"03","year":"2019","date_published":"2019-03-01T00:00:00Z","title":"Spin wave transport through electron solids and fractional quantum Hall liquids in graphene","publisher":"American Physical Society","language":[{"iso":"eng"}],"publication":"APS March Meeting 2019","issue":"2","article_processing_charge":"No","volume":64,"date_updated":"2022-02-04T13:59:47Z","oa":1,"publication_identifier":{"issn":["0003-0503"]},"extern":"1","_id":"10723","oa_version":"Published Version","quality_controlled":"1","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","citation":{"ieee":"H. Zhou, H. Polshyn, T. Tanaguchi, K. Watanabe, and A. Young, “Spin wave transport through electron solids and fractional quantum Hall liquids in graphene,” in <i>APS March Meeting 2019</i>, Boston, MA, United States, 2019, vol. 64, no. 2.","apa":"Zhou, H., Polshyn, H., Tanaguchi, T., Watanabe, K., &#38; Young, A. (2019). Spin wave transport through electron solids and fractional quantum Hall liquids in graphene. In <i>APS March Meeting 2019</i> (Vol. 64). Boston, MA, United States: American Physical Society.","chicago":"Zhou, Haoxin, Hryhoriy Polshyn, Takashi Tanaguchi, Kenji Watanabe, and Andrea Young. “Spin Wave Transport through Electron Solids and Fractional Quantum Hall Liquids in Graphene.” In <i>APS March Meeting 2019</i>, Vol. 64. American Physical Society, 2019.","mla":"Zhou, Haoxin, et al. “Spin Wave Transport through Electron Solids and Fractional Quantum Hall Liquids in Graphene.” <i>APS March Meeting 2019</i>, vol. 64, no. 2, P01.00004, American Physical Society, 2019.","ama":"Zhou H, Polshyn H, Tanaguchi T, Watanabe K, Young A. Spin wave transport through electron solids and fractional quantum Hall liquids in graphene. In: <i>APS March Meeting 2019</i>. Vol 64. American Physical Society; 2019.","ista":"Zhou H, Polshyn H, Tanaguchi T, Watanabe K, Young A. 2019. Spin wave transport through electron solids and fractional quantum Hall liquids in graphene. APS March Meeting 2019. APS: American Physical Society vol. 64, P01.00004.","short":"H. Zhou, H. Polshyn, T. Tanaguchi, K. Watanabe, A. Young, in:, APS March Meeting 2019, American Physical Society, 2019."},"day":"01","publication_status":"published","type":"conference","intvolume":"        64","abstract":[{"text":"In monolayer graphene, the interplay of electronic correlations with the internal spin- and valley- degrees of freedom leads to a complex phase diagram of isospin symmetry breaking at high magnetic fields. Recently, Wei et al. (Science (2018)) demonstrated that spin waves can be electrically generated and detected in graphene heterojunctions, allowing direct experiment access to the spin degree of freedom. Here, we apply this technique to high quality graphite-gated graphene devices showing robust fractional quantum Hall phases and isospin phase transitions. We use an edgeless Corbino geometry to eliminate the contributions of edge states to the spin-wave mediated nonlocal voltage, allowing unambiguous identification of spin wave transport signatures. Our data reveal two phases within the ν = 1 plateau. For exactly ν=1, charge is localized but spin waves propagate freely while small carrier doping completely quenches the low-energy spin-wave transport, even as those charges remain localized. We identify this new phase as a spin textured electron solid. We also find that spin-wave transport is modulated by phase transitions in the valley order that preserve spin polarization, suggesting that this technique is sensitive to both spin and valley order.","lang":"eng"}],"author":[{"last_name":"Zhou","full_name":"Zhou, Haoxin","first_name":"Haoxin"},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn","first_name":"Hryhoriy"},{"first_name":"Takashi","full_name":"Tanaguchi, Takashi","last_name":"Tanaguchi"},{"last_name":"Watanabe","full_name":"Watanabe, Kenji","first_name":"Kenji"},{"first_name":"Andrea","full_name":"Young, Andrea","last_name":"Young"}],"status":"public"},{"month":"03","date_published":"2019-03-01T00:00:00Z","publisher":"American Physical Society","language":[{"iso":"eng"}],"conference":{"start_date":"2019-03-04","end_date":"2019-03-08","name":"APS: American Physical Society","location":"Boston, MA, United States"},"date_created":"2022-02-04T12:25:04Z","day":"01","type":"conference","intvolume":"        64","status":"public","publication":"APS March Meeting 2019","issue":"2","year":"2019","title":"Normal state transport in superconducting twisted bilayer graphene","alternative_title":["Bulletin of the American Physical Society"],"main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR19/Session/V14.8"}],"article_number":"V14.00008","citation":{"chicago":"Polshyn, Hryhoriy, Yuxuan Zhang, Matthew Yankowitz, Shaowen Chen, Takashi Taniguchi, Kenji Watanabe, David E. Graf, Cory R. Dean, and Andrea Young. “Normal State Transport in Superconducting Twisted Bilayer Graphene.” In <i>APS March Meeting 2019</i>, Vol. 64. American Physical Society, 2019.","ieee":"H. Polshyn <i>et al.</i>, “Normal state transport in superconducting twisted bilayer graphene,” in <i>APS March Meeting 2019</i>, Boston, MA, United States, 2019, vol. 64, no. 2.","apa":"Polshyn, H., Zhang, Y., Yankowitz, M., Chen, S., Taniguchi, T., Watanabe, K., … Young, A. (2019). Normal state transport in superconducting twisted bilayer graphene. In <i>APS March Meeting 2019</i> (Vol. 64). Boston, MA, United States: American Physical Society.","ista":"Polshyn H, Zhang Y, Yankowitz M, Chen S, Taniguchi T, Watanabe K, Graf DE, Dean CR, Young A. 2019. Normal state transport in superconducting twisted bilayer graphene. APS March Meeting 2019. APS: American Physical Society, Bulletin of the American Physical Society, vol. 64, V14.00008.","short":"H. Polshyn, Y. Zhang, M. Yankowitz, S. Chen, T. Taniguchi, K. Watanabe, D.E. Graf, C.R. Dean, A. Young, in:, APS March Meeting 2019, American Physical Society, 2019.","ama":"Polshyn H, Zhang Y, Yankowitz M, et al. Normal state transport in superconducting twisted bilayer graphene. In: <i>APS March Meeting 2019</i>. Vol 64. American Physical Society; 2019.","mla":"Polshyn, Hryhoriy, et al. “Normal State Transport in Superconducting Twisted Bilayer Graphene.” <i>APS March Meeting 2019</i>, vol. 64, no. 2, V14.00008, American Physical Society, 2019."},"publication_status":"published","abstract":[{"lang":"eng","text":"Twisted bilayer graphene (tBLG) near the flat band condition is a versatile new platform for the study of correlated physics in 2D. Resistive states have been observed at several commensurate fillings of the flat miniband, along with superconducting states near half filling. To better understand the electronic structure of this system, we study electronic transport of graphite gated superconducting tBLG devices in the normal regime. At high magnetic fields, we observe full lifting of the spin and valley degeneracy. The transitions in the splitting of this four-fold degeneracy as a function of carrier density indicate Landau level (LL) crossings, which tilted field measurements show occur between LLs with different valley polarization. Similar LL structure measured in two devices, one with twist angle θ=1.08° at ambient pressure and one at θ=1.27° and 1.33GPa, suggests that the dimensionless combination of twist angle and interlayer coupling controls the relevant details of the band structure. In addition, we find that the temperature dependence of the resistance at B=0 shows linear growth at several hundred Ohm/K in a broad range of temperatures. We discuss the implications for modeling the scattering processes in this system."}],"author":[{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","first_name":"Hryhoriy"},{"last_name":"Zhang","full_name":"Zhang, Yuxuan","first_name":"Yuxuan"},{"first_name":"Matthew","last_name":"Yankowitz","full_name":"Yankowitz, Matthew"},{"full_name":"Chen, Shaowen","last_name":"Chen","first_name":"Shaowen"},{"first_name":"Takashi","last_name":"Taniguchi","full_name":"Taniguchi, Takashi"},{"first_name":"Kenji","last_name":"Watanabe","full_name":"Watanabe, Kenji"},{"first_name":"David E.","full_name":"Graf, David E.","last_name":"Graf"},{"full_name":"Dean, Cory R.","last_name":"Dean","first_name":"Cory R."},{"last_name":"Young","full_name":"Young, Andrea","first_name":"Andrea"}],"article_processing_charge":"No","oa":1,"volume":64,"date_updated":"2022-02-08T10:23:13Z","publication_identifier":{"issn":["0003-0503"]},"extern":"1","_id":"10724","quality_controlled":"1","oa_version":"Published Version","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9"},{"status":"public","intvolume":"        64","type":"conference","day":"01","issue":"2","publication":"APS March Meeting 2019","language":[{"iso":"eng"}],"publisher":"American Physical Society","date_published":"2019-03-01T00:00:00Z","month":"03","date_created":"2022-02-04T13:48:04Z","conference":{"start_date":"2019-03-04","location":"Boston, MA, United States","end_date":"2019-03-08","name":"APS: American Physical Society"},"author":[{"first_name":"Shaowen","last_name":"Chen","full_name":"Chen, Shaowen"},{"full_name":"Yankowitz, Matthew","last_name":"Yankowitz","first_name":"Matthew"},{"last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","first_name":"Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"last_name":"Watanabe","full_name":"Watanabe, Kenji","first_name":"Kenji"},{"full_name":"Taniguchi, Takashi","last_name":"Taniguchi","first_name":"Takashi"},{"full_name":"Graf, David E.","last_name":"Graf","first_name":"David E."},{"last_name":"Young","full_name":"Young, Andrea","first_name":"Andrea"},{"first_name":"Cory R.","full_name":"Dean, Cory R.","last_name":"Dean"}],"abstract":[{"lang":"eng","text":"Bilayer graphene with ~ 1.1 degrees twist mismatch between the layers hosts a low energy flat band in which the Coulomb interaction is large relative to the bandwidth, promoting correlated insulating states at half band filling, and superconducting (SC) phases with dome-like structure neighboring correlated insulating states. Here we show measurements of a dual-graphite-gated twisted bilayer graphene device, which minimizes charge inhomogeneity. We observe new correlated phases, including for the first time a SC pocket near half-filling of the electron-doped band and resistive states at quarter-filling of both bands that emerge in a magnetic field. Changing the layer polarization with vertical electric field reveals an unexpected competition between SC and correlated insulator phases, which we interpret to result from differences in disorder of each graphene layer and underscores the spatial inhomogeneity like twist angle as a significant source of disorder in these devices [1]."}],"publication_status":"published","citation":{"ama":"Chen S, Yankowitz M, Polshyn H, et al. Correlated insulating and superconducting phases in twisted bilayer graphene. In: <i>APS March Meeting 2019</i>. Vol 64. American Physical Society; 2019.","mla":"Chen, Shaowen, et al. “Correlated Insulating and Superconducting Phases in Twisted Bilayer Graphene.” <i>APS March Meeting 2019</i>, vol. 64, no. 2, R14.00004, American Physical Society, 2019.","short":"S. Chen, M. Yankowitz, H. Polshyn, K. Watanabe, T. Taniguchi, D.E. Graf, A. Young, C.R. Dean, in:, APS March Meeting 2019, American Physical Society, 2019.","ista":"Chen S, Yankowitz M, Polshyn H, Watanabe K, Taniguchi T, Graf DE, Young A, Dean CR. 2019. Correlated insulating and superconducting phases in twisted bilayer graphene. APS March Meeting 2019. APS: American Physical Society, Bulletin of the American Physical Society, vol. 64, R14.00004.","ieee":"S. Chen <i>et al.</i>, “Correlated insulating and superconducting phases in twisted bilayer graphene,” in <i>APS March Meeting 2019</i>, Boston, MA, United States, 2019, vol. 64, no. 2.","apa":"Chen, S., Yankowitz, M., Polshyn, H., Watanabe, K., Taniguchi, T., Graf, D. E., … Dean, C. R. (2019). Correlated insulating and superconducting phases in twisted bilayer graphene. In <i>APS March Meeting 2019</i> (Vol. 64). Boston, MA, United States: American Physical Society.","chicago":"Chen, Shaowen, Matthew Yankowitz, Hryhoriy Polshyn, Kenji Watanabe, Takashi Taniguchi, David E. Graf, Andrea Young, and Cory R. Dean. “Correlated Insulating and Superconducting Phases in Twisted Bilayer Graphene.” In <i>APS March Meeting 2019</i>, Vol. 64. American Physical Society, 2019."},"user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","oa_version":"Published Version","quality_controlled":"1","_id":"10725","publication_identifier":{"issn":["0003-0503"]},"extern":"1","oa":1,"volume":64,"date_updated":"2022-02-08T10:24:13Z","article_processing_charge":"No","title":"Correlated insulating and superconducting phases in twisted bilayer graphene","year":"2019","related_material":{"link":[{"url":"https://arxiv.org/abs/1808.07865","relation":"used_in_publication"}]},"main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR19/Session/R14.4","open_access":"1"}],"article_number":"R14.00004","alternative_title":["Bulletin of the American Physical Society"]},{"article_processing_charge":"No","oa":1,"date_updated":"2023-02-21T16:00:09Z","volume":367,"arxiv":1,"oa_version":"Preprint","quality_controlled":"1","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","acknowledgement":"The authors acknowledge discussions with A. Macdonald, Y. Saito, and M. Zaletel.","publication_identifier":{"eissn":["1095-9203"],"issn":["0036-8075"]},"extern":"1","_id":"10619","pmid":1,"citation":{"chicago":"Serlin, M., C. L. Tschirhart, Hryhoriy Polshyn, Y. Zhang, J. Zhu, K. Watanabe, T. Taniguchi, L. Balents, and A. F. Young. “Intrinsic Quantized Anomalous Hall Effect in a Moiré Heterostructure.” <i>Science</i>. American Association for the Advancement of Science, 2019. <a href=\"https://doi.org/10.1126/science.aay5533\">https://doi.org/10.1126/science.aay5533</a>.","apa":"Serlin, M., Tschirhart, C. L., Polshyn, H., Zhang, Y., Zhu, J., Watanabe, K., … Young, A. F. (2019). Intrinsic quantized anomalous Hall effect in a moiré heterostructure. <i>Science</i>. American Association for the Advancement of Science. <a href=\"https://doi.org/10.1126/science.aay5533\">https://doi.org/10.1126/science.aay5533</a>","ieee":"M. Serlin <i>et al.</i>, “Intrinsic quantized anomalous Hall effect in a moiré heterostructure,” <i>Science</i>, vol. 367, no. 6480. American Association for the Advancement of Science, pp. 900–903, 2019.","ista":"Serlin M, Tschirhart CL, Polshyn H, Zhang Y, Zhu J, Watanabe K, Taniguchi T, Balents L, Young AF. 2019. Intrinsic quantized anomalous Hall effect in a moiré heterostructure. Science. 367(6480), 900–903.","short":"M. Serlin, C.L. Tschirhart, H. Polshyn, Y. Zhang, J. Zhu, K. Watanabe, T. Taniguchi, L. Balents, A.F. Young, Science 367 (2019) 900–903.","ama":"Serlin M, Tschirhart CL, Polshyn H, et al. Intrinsic quantized anomalous Hall effect in a moiré heterostructure. <i>Science</i>. 2019;367(6480):900-903. doi:<a href=\"https://doi.org/10.1126/science.aay5533\">10.1126/science.aay5533</a>","mla":"Serlin, M., et al. “Intrinsic Quantized Anomalous Hall Effect in a Moiré Heterostructure.” <i>Science</i>, vol. 367, no. 6480, American Association for the Advancement of Science, 2019, pp. 900–03, doi:<a href=\"https://doi.org/10.1126/science.aay5533\">10.1126/science.aay5533</a>."},"publication_status":"published","author":[{"first_name":"M.","last_name":"Serlin","full_name":"Serlin, M."},{"full_name":"Tschirhart, C. L.","last_name":"Tschirhart","first_name":"C. L."},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","first_name":"Hryhoriy","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","last_name":"Polshyn"},{"first_name":"Y.","full_name":"Zhang, Y.","last_name":"Zhang"},{"first_name":"J.","full_name":"Zhu, J.","last_name":"Zhu"},{"first_name":"K.","full_name":"Watanabe, K.","last_name":"Watanabe"},{"first_name":"T.","full_name":"Taniguchi, T.","last_name":"Taniguchi"},{"full_name":"Balents, L.","last_name":"Balents","first_name":"L."},{"last_name":"Young","full_name":"Young, A. F.","first_name":"A. F."}],"keyword":["multidisciplinary"],"abstract":[{"lang":"eng","text":"The quantum anomalous Hall (QAH) effect combines topology and magnetism to produce precisely quantized Hall resistance at zero magnetic field. We report the observation of a QAH effect in twisted bilayer graphene aligned to hexagonal boron nitride. The effect is driven by intrinsic strong interactions, which polarize the electrons into a single spin- and valley-resolved moiré miniband with Chern number C = 1. In contrast to magnetically doped systems, the measured transport energy gap is larger than the Curie temperature for magnetic ordering, and quantization to within 0.1% of the von Klitzing constant persists to temperatures of several kelvin at zero magnetic field. Electrical currents as small as 1 nanoampere controllably switch the magnetic order between states of opposite polarization, forming an electrically rewritable magnetic memory."}],"main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/1907.00261"}],"related_material":{"record":[{"relation":"other","id":"10697","status":"public"},{"status":"public","relation":"other","id":"10698"},{"status":"public","id":"10699","relation":"other"}]},"doi":"10.1126/science.aay5533","year":"2019","external_id":{"pmid":["31857492"],"arxiv":["1907.00261"]},"title":"Intrinsic quantized anomalous Hall effect in a moiré heterostructure","page":"900-903","publication":"Science","issue":"6480","type":"journal_article","day":"19","status":"public","intvolume":"       367","date_created":"2022-01-13T14:21:32Z","article_type":"original","date_published":"2019-12-19T00:00:00Z","month":"12","language":[{"iso":"eng"}],"scopus_import":"1","publisher":"American Association for the Advancement of Science"},{"publication_status":"published","citation":{"apa":"Zhou, H., Polshyn, H., Taniguchi, T., Watanabe, K., &#38; Young, A. F. (2019). Solids of quantum Hall skyrmions in graphene. <i>Nature Physics</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41567-019-0729-8\">https://doi.org/10.1038/s41567-019-0729-8</a>","ieee":"H. Zhou, H. Polshyn, T. Taniguchi, K. Watanabe, and A. F. Young, “Solids of quantum Hall skyrmions in graphene,” <i>Nature Physics</i>, vol. 16, no. 2. Springer Nature, pp. 154–158, 2019.","chicago":"Zhou, H., Hryhoriy Polshyn, T. Taniguchi, K. Watanabe, and A. F. Young. “Solids of Quantum Hall Skyrmions in Graphene.” <i>Nature Physics</i>. Springer Nature, 2019. <a href=\"https://doi.org/10.1038/s41567-019-0729-8\">https://doi.org/10.1038/s41567-019-0729-8</a>.","ama":"Zhou H, Polshyn H, Taniguchi T, Watanabe K, Young AF. Solids of quantum Hall skyrmions in graphene. <i>Nature Physics</i>. 2019;16(2):154-158. doi:<a href=\"https://doi.org/10.1038/s41567-019-0729-8\">10.1038/s41567-019-0729-8</a>","mla":"Zhou, H., et al. “Solids of Quantum Hall Skyrmions in Graphene.” <i>Nature Physics</i>, vol. 16, no. 2, Springer Nature, 2019, pp. 154–58, doi:<a href=\"https://doi.org/10.1038/s41567-019-0729-8\">10.1038/s41567-019-0729-8</a>.","short":"H. Zhou, H. Polshyn, T. Taniguchi, K. Watanabe, A.F. Young, Nature Physics 16 (2019) 154–158.","ista":"Zhou H, Polshyn H, Taniguchi T, Watanabe K, Young AF. 2019. Solids of quantum Hall skyrmions in graphene. Nature Physics. 16(2), 154–158."},"author":[{"full_name":"Zhou, H.","last_name":"Zhou","first_name":"H."},{"first_name":"Hryhoriy","orcid":"0000-0001-8223-8896","last_name":"Polshyn","full_name":"Polshyn, Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"first_name":"T.","full_name":"Taniguchi, T.","last_name":"Taniguchi"},{"last_name":"Watanabe","full_name":"Watanabe, K.","first_name":"K."},{"first_name":"A. F.","last_name":"Young","full_name":"Young, A. F."}],"keyword":["General Physics and Astronomy"],"abstract":[{"text":"Partially filled Landau levels host competing electronic orders. For example, electron solids may prevail close to integer filling of the Landau levels before giving way to fractional quantum Hall liquids at higher carrier density1,2. Here, we report the observation of an electron solid with non-collinear spin texture in monolayer graphene, consistent with solidification of skyrmions3—topological spin textures characterized by quantized electrical charge4,5. We probe the spin texture of the solids using a modified Corbino geometry that allows ferromagnetic magnons to be launched and detected6,7. We find that magnon transport is highly efficient when one Landau level is filled (ν=1), consistent with quantum Hall ferromagnetic spin polarization. However, even minimal doping immediately quenches the magnon signal while leaving the vanishing low-temperature charge conductivity unchanged. Our results can be understood by the formation of a solid of charged skyrmions near ν=1, whose non-collinear spin texture leads to rapid magnon decay. Data near fractional fillings show evidence of several fractional skyrmion solids, suggesting that graphene hosts a highly tunable landscape of coupled spin and charge orders.","lang":"eng"}],"volume":16,"date_updated":"2022-01-13T15:34:44Z","article_processing_charge":"No","user_id":"ea97e931-d5af-11eb-85d4-e6957dddbf17","acknowledgement":"We acknowledge discussions with B. Halperin, C. Huang, A. Macdonald and M. Zalatel. Experimental work at UCSB was supported by the Army Research Office under awards nos. MURI W911NF-16-1-0361 and W911NF-16-1-0482. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by MEXT (Japan) and CREST (JPMJCR15F3), JST. A.F.Y. acknowledges the support of the David and Lucile Packard Foundation and and Alfred. P. Sloan Foundation.","oa_version":"None","quality_controlled":"1","_id":"10620","extern":"1","publication_identifier":{"eissn":["1745-2481"],"issn":["1745-2473"]},"year":"2019","doi":"10.1038/s41567-019-0729-8","title":"Solids of quantum Hall skyrmions in graphene","type":"journal_article","day":"16","status":"public","intvolume":"        16","page":"154-158","issue":"2","publication":"Nature Physics","date_published":"2019-12-16T00:00:00Z","article_type":"original","month":"12","language":[{"iso":"eng"}],"publisher":"Springer Nature","scopus_import":"1","date_created":"2022-01-13T14:45:16Z"}]