[{"publication":"APS March Meeting 2021","_id":"10692","author":[{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","last_name":"Polshyn","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896"},{"full_name":"Zhu, Jihang","first_name":"Jihang","last_name":"Zhu"},{"full_name":"Kumar, Manish","last_name":"Kumar","first_name":"Manish"},{"first_name":"Yuxuan","last_name":"Zhang","full_name":"Zhang, Yuxuan"},{"full_name":"Yang, Fangyuan","last_name":"Yang","first_name":"Fangyuan"},{"full_name":"Tschirhart, Charles","last_name":"Tschirhart","first_name":"Charles"},{"first_name":"Marec","last_name":"Serlin","full_name":"Serlin, Marec"},{"last_name":"Watanabe","first_name":"Kenji","full_name":"Watanabe, Kenji"},{"full_name":"Tanaguchi, Takashi","last_name":"Tanaguchi","first_name":"Takashi"},{"full_name":"MacDonald, Allan","first_name":"Allan","last_name":"MacDonald"},{"full_name":"Young, Andrea","last_name":"Young","first_name":"Andrea"}],"issue":"1","oa_version":"Published Version","date_created":"2022-01-27T09:49:48Z","article_processing_charge":"No","alternative_title":["Bulletin of the American Physical Society"],"month":"03","title":"Orbital Chern insulator states in twisted monolayer-bilayer graphene and electrical switching of topological and magnetic order","intvolume":"        66","article_number":"E42.00010","quality_controlled":"1","language":[{"iso":"eng"}],"publisher":"American Physical Society","conference":{"end_date":"2021-03-19","location":"Virtual","name":"APS: American Physical Society","start_date":"2021-03-15"},"date_updated":"2022-01-27T10:46:23Z","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.","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.","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.","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.","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."},"year":"2021","date_published":"2021-03-01T00:00:00Z","type":"conference","day":"01","publication_identifier":{"issn":["0003-0503"]},"abstract":[{"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.","lang":"eng"}],"oa":1,"volume":66,"main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR21/Session/E42.10","open_access":"1"}],"extern":"1","status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9"},{"date_published":"2021-03-01T00:00:00Z","type":"conference","publication_identifier":{"issn":["0003-0503"]},"oa":1,"main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR21/Session/L42.12","open_access":"1"}],"user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","status":"public","publication":"APS March Meeting 2021","oa_version":"None","month":"03","article_number":"L42.00012","language":[{"iso":"eng"}],"conference":{"location":"Virtual, United States","end_date":"2021-03-19","start_date":"2021-03-15","name":"APS: American Physical Society"},"date_updated":"2022-01-27T09:37:51Z","year":"2021","citation":{"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.","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.","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.","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.","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.","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."},"day":"01","abstract":[{"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.","lang":"eng"}],"acknowledgement":"I acknowledge and appreciate support from the Hertz Foundation and from the National Science Foundation Graduate Research Fellowship Program under grant 1650114.","volume":66,"extern":"1","_id":"10651","author":[{"last_name":"Tschirhart","first_name":"Charles","full_name":"Tschirhart, Charles"},{"full_name":"Serlin, Marec","first_name":"Marec","last_name":"Serlin"},{"last_name":"Polshyn","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"last_name":"Shragai","first_name":"Avi G.","full_name":"Shragai, Avi G."},{"full_name":"Xia, Zhengchao","first_name":"Zhengchao","last_name":"Xia"},{"last_name":"Zhu","first_name":"Jiacheng","full_name":"Zhu, Jiacheng"},{"full_name":"Zhang, Yuxuan","last_name":"Zhang","first_name":"Yuxuan"},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"last_name":"Taniguchi","first_name":"Takashi","full_name":"Taniguchi, Takashi"},{"full_name":"Huber, Martin E.","first_name":"Martin E.","last_name":"Huber"},{"full_name":"Young, Andrea","last_name":"Young","first_name":"Andrea"}],"issue":"1","publication_status":"published","date_created":"2022-01-20T15:43:16Z","article_processing_charge":"No","alternative_title":["Bulletin of the American Physical Society"],"title":"Probing orbital Chern ferromagnet phase in twisted bilayer graphene","intvolume":"        66","quality_controlled":"1","publisher":"American Physical Society"},{"publication":"APS March Meeting 2020","oa_version":"Published Version","month":"03","article_number":"B54. 00007","language":[{"iso":"eng"}],"conference":{"start_date":"2020-03-02","name":"APS: American Physical Society","location":"Denver, CO, United States","end_date":"2020-03-06"},"date_published":"2020-03-01T00:00:00Z","type":"conference","publication_identifier":{"issn":["0003-0503"]},"oa":1,"main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR20/Session/B54.7"}],"user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","status":"public","_id":"10693","author":[{"last_name":"Zhou","first_name":"Haoxin","full_name":"Zhou, Haoxin"},{"first_name":"Hryhoriy","last_name":"Polshyn","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"last_name":"Tanaguchi","first_name":"Takashi","full_name":"Tanaguchi, Takashi"},{"first_name":"Kenji","last_name":"Watanabe","full_name":"Watanabe, Kenji"},{"full_name":"Young, Andrea","first_name":"Andrea","last_name":"Young"}],"issue":"1","publication_status":"published","article_processing_charge":"No","date_created":"2022-01-27T10:50:10Z","title":"Sublattice resolved spin wave transport through graphene fractional quantum Hall states as a probe of isospin order","alternative_title":["Bulletin of the American Physical Society"],"intvolume":"        65","quality_controlled":"1","publisher":"American Physical Society","date_updated":"2022-01-27T10:58:38Z","citation":{"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.","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.","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.","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.","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.","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.","short":"H. Zhou, H. Polshyn, T. Tanaguchi, K. Watanabe, A. Young, in:, APS March Meeting 2020, American Physical Society, 2020."},"year":"2020","day":"01","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"}],"volume":65,"extern":"1"},{"language":[{"iso":"eng"}],"conference":{"start_date":"2020-03-02","name":"APS: American Physical Society","end_date":"2020-03-06","location":"Denver, CO, United States"},"publication":"APS March Meeting 2020","oa_version":"Published Version","article_number":"B51.00005","month":"03","main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR20/Session/B51.5","open_access":"1"}],"status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","type":"conference","date_published":"2020-03-01T00:00:00Z","publication_identifier":{"issn":["0003-0503"]},"oa":1,"quality_controlled":"1","publisher":"American Physical Society","_id":"10696","issue":"1","author":[{"last_name":"Polshyn","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"full_name":"Zhu, Jihang","last_name":"Zhu","first_name":"Jihang"},{"full_name":"Kumar, Manish","first_name":"Manish","last_name":"Kumar"},{"last_name":"Taniguchi","first_name":"Takashi","full_name":"Taniguchi, Takashi"},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"full_name":"MacDonald, Allan","first_name":"Allan","last_name":"MacDonald"},{"full_name":"Young, Andrea","first_name":"Andrea","last_name":"Young"}],"date_created":"2022-01-28T10:09:19Z","article_processing_charge":"No","publication_status":"published","intvolume":"        65","title":"Correlated states and tunable topological bands in twisted monolayer-bilayer graphene heterostructures","alternative_title":["Bulletin of the American Physical Society"],"volume":65,"extern":"1","year":"2020","citation":{"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.","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.","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.","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.","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.","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.","short":"H. Polshyn, J. Zhu, M. Kumar, T. Taniguchi, K. Watanabe, A. MacDonald, A. Young, in:, APS March Meeting 2020, American Physical Society, 2020."},"date_updated":"2022-02-08T10:22:08Z","day":"01","abstract":[{"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.","lang":"eng"}]},{"quality_controlled":"1","publisher":"American Physical Society","_id":"10699","author":[{"first_name":"Charles","last_name":"Tschirhart","full_name":"Tschirhart, Charles"},{"full_name":"Serlin, Marec","first_name":"Marec","last_name":"Serlin"},{"orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","first_name":"Hryhoriy","last_name":"Polshyn","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"full_name":"Zhang, Yuxuan","last_name":"Zhang","first_name":"Yuxuan"},{"full_name":"Zhu, Jiacheng","first_name":"Jiacheng","last_name":"Zhu"},{"first_name":"Leon","last_name":"Balents","full_name":"Balents, Leon"},{"first_name":"Martin E.","last_name":"Huber","full_name":"Huber, Martin E."},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"last_name":"Tanaguchi","first_name":"Takashi","full_name":"Tanaguchi, Takashi"},{"full_name":"Young, Andrea","last_name":"Young","first_name":"Andrea"}],"issue":"1","publication_status":"published","date_created":"2022-01-28T10:57:49Z","article_processing_charge":"No","title":"Intrinsic quantized anomalous Hall effect in a moiré heterostructure, part III: Scanning probe magnetometry","alternative_title":["Bulletin of the American Physical Society"],"intvolume":"        65","volume":65,"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.","extern":"1","date_updated":"2023-02-21T15:57:52Z","citation":{"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.","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.","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.","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.","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."},"year":"2020","external_id":{"arxiv":["1907.00261"]},"arxiv":1,"day":"01","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."}],"language":[{"iso":"eng"}],"conference":{"location":"Denver, CO, United States","end_date":"2020-03-06","name":"APS: American Physical Society","start_date":"2020-03-02"},"publication":"APS March Meeting 2020","oa_version":"Published Version","month":"03","article_number":"B59.00013","main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR20/Session/B59.13","open_access":"1"}],"related_material":{"record":[{"relation":"other","id":"10619","status":"public"}]},"status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","date_published":"2020-03-01T00:00:00Z","type":"conference","publication_identifier":{"issn":["0003-0503"]},"oa":1},{"abstract":[{"lang":"eng","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."}],"day":"01","date_updated":"2022-02-08T10:25:30Z","year":"2019","citation":{"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.","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.","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.","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.","short":"M. Serlin, C. Tschirhart, H. Polshyn, J. Zhu, M.E. Huber, A. Young, in:, APS March Meeting 2019, 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.","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."},"extern":"1","volume":64,"title":"Direct Imaging of magnetic structure in twisted bilayer graphene with scanning nanoSQUID-On-Tip microscopy","alternative_title":["Bulletin of the American Physical Society"],"intvolume":"        64","publication_status":"published","article_processing_charge":"No","date_created":"2022-02-04T11:54:21Z","author":[{"full_name":"Serlin, Marec","last_name":"Serlin","first_name":"Marec"},{"last_name":"Tschirhart","first_name":"Charles","full_name":"Tschirhart, Charles"},{"last_name":"Polshyn","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"first_name":"Jiacheng","last_name":"Zhu","full_name":"Zhu, Jiacheng"},{"last_name":"Huber","first_name":"Martin E.","full_name":"Huber, Martin E."},{"last_name":"Young","first_name":"Andrea","full_name":"Young, Andrea"}],"issue":"2","_id":"10722","publisher":"American Physical Society","quality_controlled":"1","oa":1,"publication_identifier":{"issn":["0003-0503"]},"date_published":"2019-03-01T00:00:00Z","type":"conference","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","status":"public","main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR19/Session/L14.6","open_access":"1"}],"month":"03","article_number":"L14.00006","oa_version":"Published Version","publication":"APS March Meeting 2019","conference":{"start_date":"2019-03-04","name":"APS: American Physical Society","end_date":"2019-03-08","location":"Boston, MA, United States"},"language":[{"iso":"eng"}]},{"language":[{"iso":"eng"}],"quality_controlled":"1","conference":{"name":"APS: American Physical Society","start_date":"2019-03-04","location":"Boston, MA, United States","end_date":"2019-03-08"},"publisher":"American Physical Society","author":[{"full_name":"Zhou, Haoxin","first_name":"Haoxin","last_name":"Zhou"},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","first_name":"Hryhoriy","last_name":"Polshyn"},{"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"}],"issue":"2","publication":"APS March Meeting 2019","_id":"10723","month":"03","title":"Spin wave transport through electron solids and fractional quantum Hall liquids in graphene","article_number":"P01.00004","intvolume":"        64","oa_version":"Published Version","publication_status":"published","article_processing_charge":"No","date_created":"2022-02-04T12:14:02Z","extern":"1","status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","volume":64,"main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR19/Session/P01.4"}],"date_published":"2019-03-01T00:00:00Z","type":"conference","date_updated":"2022-02-04T13:59:47Z","citation":{"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.","short":"H. Zhou, H. Polshyn, T. Tanaguchi, K. Watanabe, A. Young, in:, APS March Meeting 2019, 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.","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.","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.","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.","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."},"year":"2019","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"}],"oa":1,"publication_identifier":{"issn":["0003-0503"]},"day":"01"},{"extern":"1","volume":64,"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."}],"day":"01","date_updated":"2022-02-08T10:23:13Z","citation":{"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.","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.","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.","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.","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.","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."},"year":"2019","publisher":"American Physical Society","quality_controlled":"1","title":"Normal state transport in superconducting twisted bilayer graphene","alternative_title":["Bulletin of the American Physical Society"],"intvolume":"        64","publication_status":"published","date_created":"2022-02-04T12:25:04Z","article_processing_charge":"No","author":[{"full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","last_name":"Polshyn","first_name":"Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"full_name":"Zhang, Yuxuan","first_name":"Yuxuan","last_name":"Zhang"},{"first_name":"Matthew","last_name":"Yankowitz","full_name":"Yankowitz, Matthew"},{"full_name":"Chen, Shaowen","last_name":"Chen","first_name":"Shaowen"},{"full_name":"Taniguchi, Takashi","first_name":"Takashi","last_name":"Taniguchi"},{"first_name":"Kenji","last_name":"Watanabe","full_name":"Watanabe, Kenji"},{"full_name":"Graf, David E.","first_name":"David E.","last_name":"Graf"},{"first_name":"Cory R.","last_name":"Dean","full_name":"Dean, Cory R."},{"full_name":"Young, Andrea","last_name":"Young","first_name":"Andrea"}],"issue":"2","_id":"10724","status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR19/Session/V14.8"}],"oa":1,"publication_identifier":{"issn":["0003-0503"]},"date_published":"2019-03-01T00:00:00Z","type":"conference","conference":{"location":"Boston, MA, United States","end_date":"2019-03-08","name":"APS: American Physical Society","start_date":"2019-03-04"},"language":[{"iso":"eng"}],"month":"03","article_number":"V14.00008","oa_version":"Published Version","publication":"APS March Meeting 2019"},{"extern":"1","volume":64,"year":"2019","citation":{"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.","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.","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.","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.","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.","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.","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."},"date_updated":"2022-02-08T10:24:13Z","abstract":[{"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].","lang":"eng"}],"day":"01","quality_controlled":"1","publisher":"American Physical Society","issue":"2","author":[{"full_name":"Chen, Shaowen","last_name":"Chen","first_name":"Shaowen"},{"last_name":"Yankowitz","first_name":"Matthew","full_name":"Yankowitz, Matthew"},{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","last_name":"Polshyn","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896"},{"full_name":"Watanabe, Kenji","last_name":"Watanabe","first_name":"Kenji"},{"full_name":"Taniguchi, Takashi","first_name":"Takashi","last_name":"Taniguchi"},{"full_name":"Graf, David E.","last_name":"Graf","first_name":"David E."},{"full_name":"Young, Andrea","last_name":"Young","first_name":"Andrea"},{"full_name":"Dean, Cory R.","first_name":"Cory R.","last_name":"Dean"}],"_id":"10725","intvolume":"        64","title":"Correlated insulating and superconducting phases in twisted bilayer graphene","alternative_title":["Bulletin of the American Physical Society"],"date_created":"2022-02-04T13:48:04Z","article_processing_charge":"No","publication_status":"published","related_material":{"link":[{"url":"https://arxiv.org/abs/1808.07865","relation":"used_in_publication"}]},"status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR19/Session/R14.4","open_access":"1"}],"type":"conference","date_published":"2019-03-01T00:00:00Z","oa":1,"publication_identifier":{"issn":["0003-0503"]},"language":[{"iso":"eng"}],"conference":{"location":"Boston, MA, United States","end_date":"2019-03-08","start_date":"2019-03-04","name":"APS: American Physical Society"},"publication":"APS March Meeting 2019","article_number":"R14.00004","month":"03","oa_version":"Published Version"},{"publication":"APS March Meeting 2017","oa_version":"Published Version","month":"03","article_number":"P39.00011","language":[{"iso":"eng"}],"conference":{"start_date":"2017-03-13","name":"APS: American Physical Society","end_date":"2017-03-17","location":"New Orleans, LA, United States"},"date_published":"2017-03-01T00:00:00Z","type":"conference","publication_identifier":{"issn":["0003-0503"]},"oa":1,"main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR17/Session/P39.11","open_access":"1"}],"status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","_id":"10745","author":[{"last_name":"Polshyn","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"last_name":"Naibert","first_name":"Tyler","full_name":"Naibert, Tyler"},{"last_name":"Budakian","first_name":"Raffi","full_name":"Budakian, Raffi"}],"issue":"4","publication_status":"published","date_created":"2022-02-08T09:49:17Z","article_processing_charge":"No","alternative_title":["Bulletin of the American Physical Society"],"title":" Probing and controlling fluxoid states in multiply-connected mesoscopic superconducting structures","intvolume":"        62","quality_controlled":"1","publisher":"American Physical Society","date_updated":"2022-02-08T10:44:35Z","citation":{"ama":"Polshyn H, Naibert T, Budakian R.  Probing and controlling fluxoid states in multiply-connected mesoscopic superconducting structures. In: <i>APS March Meeting 2017</i>. Vol 62. American Physical Society; 2017.","apa":"Polshyn, H., Naibert, T., &#38; Budakian, R. (2017).  Probing and controlling fluxoid states in multiply-connected mesoscopic superconducting structures. In <i>APS March Meeting 2017</i> (Vol. 62). New Orleans, LA, United States: American Physical Society.","ieee":"H. Polshyn, T. Naibert, and R. Budakian, “ Probing and controlling fluxoid states in multiply-connected mesoscopic superconducting structures,” in <i>APS March Meeting 2017</i>, New Orleans, LA, United States, 2017, vol. 62, no. 4.","chicago":"Polshyn, Hryhoriy, Tyler Naibert, and Raffi Budakian. “ Probing and Controlling Fluxoid States in Multiply-Connected Mesoscopic Superconducting Structures.” In <i>APS March Meeting 2017</i>, Vol. 62. American Physical Society, 2017.","short":"H. Polshyn, T. Naibert, R. Budakian, in:, APS March Meeting 2017, American Physical Society, 2017.","mla":"Polshyn, Hryhoriy, et al. “ Probing and Controlling Fluxoid States in Multiply-Connected Mesoscopic Superconducting Structures.” <i>APS March Meeting 2017</i>, vol. 62, no. 4, P39.00011, American Physical Society, 2017.","ista":"Polshyn H, Naibert T, Budakian R. 2017.  Probing and controlling fluxoid states in multiply-connected mesoscopic superconducting structures. APS March Meeting 2017. APS: American Physical Society, Bulletin of the American Physical Society, vol. 62, P39.00011."},"year":"2017","day":"01","abstract":[{"text":"New ways to investigate and manipulate fluxoid and vortex states of mesoscopic superconducting structures are of great interest. The states with multiple vortices or winding numbers could be useful for the study of vortex interactions and interference effects, the braiding of Majorana bound states by winding vortices, and the development of novel superconducting devices. We demonstrate a methodology based on magnetic force microscopy that allows us to induce, probe and control fluxoid states in thin wall structures comprised of multiple loops. By using micro-magnet as a source of inhomogeneous magnetic field, we can efficiently explore the configuration space of fluxoid states. Scanning over the structure reveals the energy crossing points of the lowest laying fluxoid states. This is due the strong interaction of cantilever with thermally activated fluxoid transitions at points of degeneracy. We show that measured patterns of fluxoid transitions allow to identify the states, investigate their energetics, and manipulate them. Further, we show that the dynamics of driven fluxoid transitions can be described by stochastic resonance model, which provides a unique way of measuring fluxoid transition rate and related energy barrier for chosen transitions even in complicated structures","lang":"eng"}],"volume":62,"extern":"1"},{"main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR16/Session/E25.7","open_access":"1"}],"user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","status":"public","date_published":"2016-03-01T00:00:00Z","type":"conference","publication_identifier":{"issn":["0003-0503"]},"oa":1,"language":[{"iso":"eng"}],"conference":{"location":"Baltimore, MD, United States","end_date":"2016-03-18","start_date":"2016-03-14","name":"APS: American Physical Society"},"publication":"APS March Meeting 2016","oa_version":"Published Version","month":"03","article_number":"E25.00007","volume":61,"extern":"1","date_updated":"2022-02-08T10:44:06Z","year":"2016","citation":{"ista":"Polshyn H, Naibert T, Chua V, Budakian R. 2016. Study of vortex states and dynamics in mesoscopic superconducting samples with MFM. APS March Meeting 2016. APS: American Physical Society, Bulletin of the American Physical Society, vol. 61, E25.00007.","short":"H. Polshyn, T. Naibert, V. Chua, R. Budakian, in:, APS March Meeting 2016, American Physical Society, 2016.","mla":"Polshyn, Hryhoriy, et al. “Study of Vortex States and Dynamics in Mesoscopic Superconducting Samples with MFM.” <i>APS March Meeting 2016</i>, vol. 61, no. 2, E25.00007, American Physical Society, 2016.","ieee":"H. Polshyn, T. Naibert, V. Chua, and R. Budakian, “Study of vortex states and dynamics in mesoscopic superconducting samples with MFM,” in <i>APS March Meeting 2016</i>, Baltimore, MD, United States, 2016, vol. 61, no. 2.","chicago":"Polshyn, Hryhoriy, Tyler Naibert, Victor Chua, and Raffi Budakian. “Study of Vortex States and Dynamics in Mesoscopic Superconducting Samples with MFM.” In <i>APS March Meeting 2016</i>, Vol. 61. American Physical Society, 2016.","ama":"Polshyn H, Naibert T, Chua V, Budakian R. Study of vortex states and dynamics in mesoscopic superconducting samples with MFM. In: <i>APS March Meeting 2016</i>. Vol 61. American Physical Society; 2016.","apa":"Polshyn, H., Naibert, T., Chua, V., &#38; Budakian, R. (2016). Study of vortex states and dynamics in mesoscopic superconducting samples with MFM. In <i>APS March Meeting 2016</i> (Vol. 61). Baltimore, MD, United States: American Physical Society."},"day":"01","abstract":[{"lang":"eng","text":"Vortex states in superconducting (SC) structures, their dynamics and ways to manipulate them are topics of great interest. We report a new method of magnetic force microscopy (MFM) that allows the study of vortex states in mesoscopic SC samples. For the case of a SC ring, which is biased to a half-integer flux quantum, the flux modulation through the ring caused by the motion of the magnetic tip drives the ring between two consecutive fluxoid states. The corresponding current switching in the ring produces strong position-dependent forces on the cantilever. In the regime where the frequency of the thermally activated jumps between fluxoid states is close to the frequency of the cantilever, large changes in the cantilever frequency and dissipation are observed. This effect may be understood as a stochastic resonance (SR) process. These changes in the cantilever’s mechanical properties are used to “image” the barrier energies between fluxoid states. Additionally, SR imaging of the barrier energies are used to study the effect of the locally applied magnetic field from the MFM tip on the barrier heights. We report the results of measurements for Al rings. Further, the same imaging technique can be applied to more sophisticated SC structures such as arrays of Josephson junctions."}],"quality_controlled":"1","publisher":"American Physical Society","_id":"10746","author":[{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","last_name":"Polshyn","first_name":"Hryhoriy"},{"last_name":"Naibert","first_name":"Tyler","full_name":"Naibert, Tyler"},{"full_name":"Chua, Victor","first_name":"Victor","last_name":"Chua"},{"last_name":"Budakian","first_name":"Raffi","full_name":"Budakian, Raffi"}],"issue":"2","publication_status":"published","date_created":"2022-02-08T09:55:09Z","article_processing_charge":"No","title":"Study of vortex states and dynamics in mesoscopic superconducting samples with MFM","alternative_title":["Bulletin of the American Physical Society"],"intvolume":"        61"},{"intvolume":"        61","title":"Stochastic resonance magnetic force microscopy imaging of Josephson arrays","alternative_title":["Bulletin of the American Physical Society"],"date_created":"2022-02-08T10:10:39Z","article_processing_charge":"No","publication_status":"published","issue":"2","author":[{"last_name":"Naibert","first_name":"Tyler","full_name":"Naibert, Tyler"},{"full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","last_name":"Polshyn","first_name":"Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"first_name":"Brian","last_name":"Wolin","full_name":"Wolin, Brian"},{"last_name":"Durkin","first_name":"Malcolm","full_name":"Durkin, Malcolm"},{"full_name":"Garrido Menacho, Rita","last_name":"Garrido Menacho","first_name":"Rita"},{"full_name":"Shem, Ian Mondragon","first_name":"Ian Mondragon","last_name":"Shem"},{"full_name":"Chua, Victor","last_name":"Chua","first_name":"Victor"},{"first_name":"Taylor","last_name":"Hughes","full_name":"Hughes, Taylor"},{"last_name":"Mason","first_name":"Nadya","full_name":"Mason, Nadya"},{"full_name":"Budakian, Raffi","first_name":"Raffi","last_name":"Budakian"}],"_id":"10747","publisher":"American Physical Society","quality_controlled":"1","abstract":[{"text":"Vortex interactions are key to explaining the behavior of many two dimensional superconducting systems. We report on the development of a technique to locally probe vortex interactions in a 2D array of Josephson junctions. Scanning a magnetic tip attached to an ultra-soft cantilever over the array produces changes in the frequency of the cantilever along certain lines, forming geometric patterns in the scans. Different tip-surface separations and external magnetic fields produce a number of different patterns. These patterns correspond to tip locations in which two configurations of vortices in the lattice have degenerate energies. By imaging the locations of these degeneracies, information on the local vortex interactions may be obtained.","lang":"eng"}],"day":"01","citation":{"ama":"Naibert T, Polshyn H, Wolin B, et al. Stochastic resonance magnetic force microscopy imaging of Josephson arrays. In: <i>APS March Meeting 2016</i>. Vol 61. American Physical Society; 2016.","apa":"Naibert, T., Polshyn, H., Wolin, B., Durkin, M., Garrido Menacho, R., Shem, I. M., … Budakian, R. (2016). Stochastic resonance magnetic force microscopy imaging of Josephson arrays. In <i>APS March Meeting 2016</i> (Vol. 61). Baltimore, MD, United States: American Physical Society.","chicago":"Naibert, Tyler, Hryhoriy Polshyn, Brian Wolin, Malcolm Durkin, Rita Garrido Menacho, Ian Mondragon Shem, Victor Chua, Taylor Hughes, Nadya Mason, and Raffi Budakian. “Stochastic Resonance Magnetic Force Microscopy Imaging of Josephson Arrays.” In <i>APS March Meeting 2016</i>, Vol. 61. American Physical Society, 2016.","ieee":"T. Naibert <i>et al.</i>, “Stochastic resonance magnetic force microscopy imaging of Josephson arrays,” in <i>APS March Meeting 2016</i>, Baltimore, MD, United States, 2016, vol. 61, no. 2.","mla":"Naibert, Tyler, et al. “Stochastic Resonance Magnetic Force Microscopy Imaging of Josephson Arrays.” <i>APS March Meeting 2016</i>, vol. 61, no. 2, H25.00006, American Physical Society, 2016.","short":"T. Naibert, H. Polshyn, B. Wolin, M. Durkin, R. Garrido Menacho, I.M. Shem, V. Chua, T. Hughes, N. Mason, R. Budakian, in:, APS March Meeting 2016, American Physical Society, 2016.","ista":"Naibert T, Polshyn H, Wolin B, Durkin M, Garrido Menacho R, Shem IM, Chua V, Hughes T, Mason N, Budakian R. 2016. Stochastic resonance magnetic force microscopy imaging of Josephson arrays. APS March Meeting 2016. APS: American Physical Society, Bulletin of the American Physical Society, vol. 61, H25.00006."},"year":"2016","date_updated":"2022-02-08T10:43:33Z","extern":"1","volume":61,"article_number":"H25.00006","month":"03","oa_version":"Published Version","publication":"APS March Meeting 2016","conference":{"start_date":"2016-03-14","name":"APS: American Physical Society","end_date":"2016-03-18","location":"Baltimore, MD, United States"},"language":[{"iso":"eng"}],"oa":1,"publication_identifier":{"issn":["0003-0503"]},"type":"conference","date_published":"2016-03-01T00:00:00Z","status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR16/Session/H25.6"}]},{"status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR15/Event/238442"}],"type":"conference","date_published":"2015-03-01T00:00:00Z","oa":1,"publication_identifier":{"issn":["0003-0503"]},"language":[{"iso":"eng"}],"conference":{"end_date":"2015-03-06","location":"San Antonio, TX, United States","start_date":"2015-03-02","name":"APS: American Physical Society"},"publication":"APS March Meeting 2015","article_number":"G16.00009","month":"03","oa_version":"Published Version","extern":"1","volume":60,"year":"2015","citation":{"apa":"Polshyn, H., Zhang, C., Naibert, T., Eckstein, J., &#38; Budakian, R. (2015). Study of Fe (Se, Te) micron-sized rings by magnetic force microscopy. In <i>APS March Meeting 2015</i> (Vol. 60). San Antonio, TX, United States: American Physical Society.","ama":"Polshyn H, Zhang C, Naibert T, Eckstein J, Budakian R. Study of Fe (Se, Te) micron-sized rings by magnetic force microscopy. In: <i>APS March Meeting 2015</i>. Vol 60. American Physical Society; 2015.","chicago":"Polshyn, Hryhoriy, Can Zhang, Tyler Naibert, James Eckstein, and Raffi Budakian. “Study of Fe (Se, Te) Micron-Sized Rings by Magnetic Force Microscopy.” In <i>APS March Meeting 2015</i>, Vol. 60. American Physical Society, 2015.","ieee":"H. Polshyn, C. Zhang, T. Naibert, J. Eckstein, and R. Budakian, “Study of Fe (Se, Te) micron-sized rings by magnetic force microscopy,” in <i>APS March Meeting 2015</i>, San Antonio, TX, United States, 2015, vol. 60, no. 1.","short":"H. Polshyn, C. Zhang, T. Naibert, J. Eckstein, R. Budakian, in:, APS March Meeting 2015, American Physical Society, 2015.","mla":"Polshyn, Hryhoriy, et al. “Study of Fe (Se, Te) Micron-Sized Rings by Magnetic Force Microscopy.” <i>APS March Meeting 2015</i>, vol. 60, no. 1, G16.00009, American Physical Society, 2015.","ista":"Polshyn H, Zhang C, Naibert T, Eckstein J, Budakian R. 2015. Study of Fe (Se, Te) micron-sized rings by magnetic force microscopy. APS March Meeting 2015. APS: American Physical Society, Bulletin of the American Physical Society, vol. 60, G16.00009."},"date_updated":"2022-02-08T10:42:53Z","abstract":[{"lang":"eng","text":"The study of fluxoid states and fluxoid dynamics in mesoscopic iron-based superconducting rings is valuable for characterizing the basic properties of the superconductor, and may also provide important insight into the superconducting paring symmetry. We report the fabrications of micron-sized rings and disks from thin films of Fe(Se, Te) grown by molecular beam epitaxy. In order to study fluxoid states in rings we developed a custom-tailored version of magnetic force microscopy (MFM). This technique has a number of qualitative advantages for working with mesoscopic superconducting samples in comparison to the conventional MFM and other imaging techniques. We observed metastable fluxoid states in rings of different sizes. Thermally activated fluxoid dynamics of these states was studied and modeled. In addition, we found different regimes of interaction between Fe(Se, Te) ring and MFM tip which are explained. Possibilities of the existence of exotic vortex states and proposals for experiments to test the symmetry of the superconducting order parameter in iron based superconductors are analyzed."}],"day":"01","quality_controlled":"1","publisher":"American Physical Society","issue":"1","author":[{"id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48","first_name":"Hryhoriy","last_name":"Polshyn","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy"},{"last_name":"Zhang","first_name":"Can","full_name":"Zhang, Can"},{"first_name":"Tyler","last_name":"Naibert","full_name":"Naibert, Tyler"},{"last_name":"Eckstein","first_name":"James","full_name":"Eckstein, James"},{"last_name":"Budakian","first_name":"Raffi","full_name":"Budakian, Raffi"}],"_id":"10748","intvolume":"        60","alternative_title":["Bulletin of the American Physical Society"],"title":"Study of Fe (Se, Te) micron-sized rings by magnetic force microscopy","date_created":"2022-02-08T10:17:09Z","article_processing_charge":"No","publication_status":"published"},{"volume":58,"acknowledgement":"This work was supported by the Center for Emergent Superconductivity, an Energy Frontier Research Center funded by the US DOE, Office of Science.","extern":"1","date_updated":"2022-02-08T10:48:06Z","citation":{"ista":"Polshyn H, Budakian R, Gu G. 2013. Cantilever micro-susceptometry of mesoscopic Bi2212 samples. APS March Meeting 2013. APS: American Physical Society, Bulletin of the American Physical Society, vol. 58, N36.00001.","short":"H. Polshyn, R. Budakian, G. Gu, in:, APS March Meeting 2013, American Physical Society, 2013.","mla":"Polshyn, Hryhoriy, et al. “Cantilever Micro-Susceptometry of Mesoscopic Bi2212 Samples.” <i>APS March Meeting 2013</i>, vol. 58, no. 1, N36.00001, American Physical Society, 2013.","chicago":"Polshyn, Hryhoriy, Raffi Budakian, and Genda Gu. “Cantilever Micro-Susceptometry of Mesoscopic Bi2212 Samples.” In <i>APS March Meeting 2013</i>, Vol. 58. American Physical Society, 2013.","ieee":"H. Polshyn, R. Budakian, and G. Gu, “Cantilever micro-susceptometry of mesoscopic Bi2212 samples,” in <i>APS March Meeting 2013</i>, Baltimore, MD, United States, 2013, vol. 58, no. 1.","apa":"Polshyn, H., Budakian, R., &#38; Gu, G. (2013). Cantilever micro-susceptometry of mesoscopic Bi2212 samples. In <i>APS March Meeting 2013</i> (Vol. 58). Baltimore, MD, United States: American Physical Society.","ama":"Polshyn H, Budakian R, Gu G. Cantilever micro-susceptometry of mesoscopic Bi2212 samples. In: <i>APS March Meeting 2013</i>. Vol 58. American Physical Society; 2013."},"year":"2013","day":"01","abstract":[{"text":"Fluxoid quantization provides a direct means to study phase coherence. In cuprate superconductors, there have been observations which suggest that phase coherent superconducting fluctuations may persist at temperatures significantly above Tc. The focus of this work is to study the vortex states in mesoscopic cuprate superconducting samples to directly probe phase coherence over a wide range of temperatures. We present cantilever torque susceptometry measurements of micron and sub-micron size Bi2212 rings and disks. The high sensitivity of this technique allowed observation of transitions between different fluxoid states of a single ring, and the discrete vortex states of micron size disks. The dependence of magnetic susceptibility on diameter and wall thickness of the ring was investigated. Measurements were made at different values of the in-plane magnetic field, and over a wide range of temperatures.","lang":"eng"}],"quality_controlled":"1","publisher":"American Physical Society","_id":"10749","author":[{"first_name":"Hryhoriy","last_name":"Polshyn","orcid":"0000-0001-8223-8896","full_name":"Polshyn, Hryhoriy","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"full_name":"Budakian, Raffi","last_name":"Budakian","first_name":"Raffi"},{"full_name":"Gu, Genda","first_name":"Genda","last_name":"Gu"}],"issue":"1","publication_status":"published","article_processing_charge":"No","date_created":"2022-02-08T10:34:29Z","alternative_title":["Bulletin of the American Physical Society"],"title":"Cantilever micro-susceptometry of mesoscopic Bi2212 samples","intvolume":"        58","main_file_link":[{"url":"https://meetings.aps.org/Meeting/MAR13/Event/186873","open_access":"1"}],"status":"public","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","date_published":"2013-03-01T00:00:00Z","type":"conference","publication_identifier":{"issn":["0003-0503"]},"oa":1,"language":[{"iso":"eng"}],"conference":{"location":"Baltimore, MD, United States","end_date":"2013-03-22","name":"APS: American Physical Society","start_date":"2013-03-18"},"publication":"APS March Meeting 2013","oa_version":"Published Version","month":"03","article_number":"N36.00001"},{"user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","status":"public","main_file_link":[{"open_access":"1","url":"https://meetings.aps.org/Meeting/MAR12/Event/167014"}],"oa":1,"publication_identifier":{"issn":["0003-0503"]},"type":"conference","date_published":"2012-02-01T00:00:00Z","conference":{"start_date":"2012-02-27","name":"APS: American Physical Society","location":"Boston, MA, United States","end_date":"2012-03-02"},"language":[{"iso":"eng"}],"article_number":"X21.00008","month":"02","oa_version":"Published Version","publication":"APS March Meeting 2012","extern":"1","acknowledgement":"This work was supported by the Center for Emergent Superconductivity, an Energy Frontier Research Center funded by the U.S. DOE, Office of Science, under Award No. DE-AC0298CH1088.","volume":57,"abstract":[{"text":"The goal of this work is to study the superconducting coherence length in the fluctuation regime in cuprate superconductors. In this work we present cantilever torque magnetometry measurements of micron-size BSCCO flakes patterned with arrays of nanometer scale rings or holes. Using ultrasensitive dynamic torque magnetometry, oscillations in magnetization are observed near Tc as a function of the applied magnetic flux threading the array. Special effort was made to detect the oscillations in magnetization at temperatures above Tc, where the Nernst effect and magnetization measurements suggest the possibility of pairing. To constrain the magnitude of the coherence length in the fluctuation regime, we will present the dependence of the amplitude of the h/2e period oscillations as a function of temperature and hole size.","lang":"eng"}],"day":"01","citation":{"ieee":"H. Polshyn and R. Budakian, “Cantilever torque magnetometry study of multiply connected BSCCO arrays near Tc,” in <i>APS March Meeting 2012</i>, Boston, MA, United States, 2012, vol. 57, no. 1.","chicago":"Polshyn, Hryhoriy, and Raffi Budakian. “Cantilever Torque Magnetometry Study of Multiply Connected BSCCO Arrays near Tc.” In <i>APS March Meeting 2012</i>, Vol. 57. American Physical Society, 2012.","ama":"Polshyn H, Budakian R. Cantilever torque magnetometry study of multiply connected BSCCO arrays near Tc. In: <i>APS March Meeting 2012</i>. Vol 57. American Physical Society; 2012.","apa":"Polshyn, H., &#38; Budakian, R. (2012). Cantilever torque magnetometry study of multiply connected BSCCO arrays near Tc. In <i>APS March Meeting 2012</i> (Vol. 57). Boston, MA, United States: American Physical Society.","ista":"Polshyn H, Budakian R. 2012. Cantilever torque magnetometry study of multiply connected BSCCO arrays near Tc. APS March Meeting 2012. APS: American Physical Society, Bulletin of the American Physical Society, vol. 57, X21.00008.","short":"H. Polshyn, R. Budakian, in:, APS March Meeting 2012, American Physical Society, 2012.","mla":"Polshyn, Hryhoriy, and Raffi Budakian. “Cantilever Torque Magnetometry Study of Multiply Connected BSCCO Arrays near Tc.” <i>APS March Meeting 2012</i>, vol. 57, no. 1, X21.00008, American Physical Society, 2012."},"year":"2012","date_updated":"2022-02-08T10:48:01Z","publisher":"American Physical Society","quality_controlled":"1","intvolume":"        57","alternative_title":["Bulletin of the American Physical Society"],"title":"Cantilever torque magnetometry study of multiply connected BSCCO arrays near Tc","date_created":"2022-02-08T10:39:08Z","article_processing_charge":"No","publication_status":"published","issue":"1","author":[{"last_name":"Polshyn","first_name":"Hryhoriy","full_name":"Polshyn, Hryhoriy","orcid":"0000-0001-8223-8896","id":"edfc7cb1-526e-11ec-b05a-e6ecc27e4e48"},{"last_name":"Budakian","first_name":"Raffi","full_name":"Budakian, Raffi"}],"_id":"10750"}]