--- _id: '7790' abstract: - lang: eng text: "We prove a lower bound for the free energy (per unit volume) of the two-dimensional Bose gas in the thermodynamic limit. We show that the free energy at density \U0001D70C and inverse temperature \U0001D6FD differs from the one of the noninteracting system by the correction term \U0001D70B\U0001D70C\U0001D70C\U0001D6FD\U0001D6FD . Here, is the scattering length of the interaction potential, and \U0001D6FD is the inverse Berezinskii–Kosterlitz–Thouless critical temperature for superfluidity. The result is valid in the dilute limit \U0001D70C and if \U0001D6FD\U0001D70C ." article_number: e20 article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 - first_name: Simon full_name: Mayer, Simon id: 30C4630A-F248-11E8-B48F-1D18A9856A87 last_name: Mayer - first_name: Robert full_name: Seiringer, Robert id: 4AFD0470-F248-11E8-B48F-1D18A9856A87 last_name: Seiringer orcid: 0000-0002-6781-0521 citation: ama: Deuchert A, Mayer S, Seiringer R. The free energy of the two-dimensional dilute Bose gas. I. Lower bound. Forum of Mathematics, Sigma. 2020;8. doi:10.1017/fms.2020.17 apa: Deuchert, A., Mayer, S., & Seiringer, R. (2020). The free energy of the two-dimensional dilute Bose gas. I. Lower bound. Forum of Mathematics, Sigma. Cambridge University Press. https://doi.org/10.1017/fms.2020.17 chicago: Deuchert, Andreas, Simon Mayer, and Robert Seiringer. “The Free Energy of the Two-Dimensional Dilute Bose Gas. I. Lower Bound.” Forum of Mathematics, Sigma. Cambridge University Press, 2020. https://doi.org/10.1017/fms.2020.17. ieee: A. Deuchert, S. Mayer, and R. Seiringer, “The free energy of the two-dimensional dilute Bose gas. I. Lower bound,” Forum of Mathematics, Sigma, vol. 8. Cambridge University Press, 2020. ista: Deuchert A, Mayer S, Seiringer R. 2020. The free energy of the two-dimensional dilute Bose gas. I. Lower bound. Forum of Mathematics, Sigma. 8, e20. mla: Deuchert, Andreas, et al. “The Free Energy of the Two-Dimensional Dilute Bose Gas. I. Lower Bound.” Forum of Mathematics, Sigma, vol. 8, e20, Cambridge University Press, 2020, doi:10.1017/fms.2020.17. short: A. Deuchert, S. Mayer, R. Seiringer, Forum of Mathematics, Sigma 8 (2020). date_created: 2020-05-03T22:00:48Z date_published: 2020-03-14T00:00:00Z date_updated: 2023-08-21T06:18:49Z day: '14' ddc: - '510' department: - _id: RoSe doi: 10.1017/fms.2020.17 ec_funded: 1 external_id: arxiv: - '1910.03372' isi: - '000527342000001' file: - access_level: open_access checksum: 8a64da99d107686997876d7cad8cfe1e content_type: application/pdf creator: dernst date_created: 2020-05-04T12:02:41Z date_updated: 2020-07-14T12:48:03Z file_id: '7797' file_name: 2020_ForumMath_Deuchert.pdf file_size: 692530 relation: main_file file_date_updated: 2020-07-14T12:48:03Z has_accepted_license: '1' intvolume: ' 8' isi: 1 language: - iso: eng month: '03' oa: 1 oa_version: Published Version project: - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems publication: Forum of Mathematics, Sigma publication_identifier: eissn: - '20505094' publication_status: published publisher: Cambridge University Press quality_controlled: '1' related_material: record: - id: '7524' relation: earlier_version status: public scopus_import: '1' status: public title: The free energy of the two-dimensional dilute Bose gas. I. Lower bound tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 8 year: '2020' ... --- _id: '8587' abstract: - lang: eng text: Inspired by the possibility to experimentally manipulate and enhance chemical reactivity in helium nanodroplets, we investigate the effective interaction and the resulting correlations between two diatomic molecules immersed in a bath of bosons. By analogy with the bipolaron, we introduce the biangulon quasiparticle describing two rotating molecules that align with respect to each other due to the effective attractive interaction mediated by the excitations of the bath. We study this system in different parameter regimes and apply several theoretical approaches to describe its properties. Using a Born–Oppenheimer approximation, we investigate the dependence of the effective intermolecular interaction on the rotational state of the two molecules. In the strong-coupling regime, a product-state ansatz shows that the molecules tend to have a strong alignment in the ground state. To investigate the system in the weak-coupling regime, we apply a one-phonon excitation variational ansatz, which allows us to access the energy spectrum. In comparison to the angulon quasiparticle, the biangulon shows shifted angulon instabilities and an additional spectral instability, where resonant angular momentum transfer between the molecules and the bath takes place. These features are proposed as an experimentally observable signature for the formation of the biangulon quasiparticle. Finally, by using products of single angulon and bare impurity wave functions as basis states, we introduce a diagonalization scheme that allows us to describe the transition from two separated angulons to a biangulon as a function of the distance between the two molecules. acknowledgement: We are grateful to Areg Ghazaryan for valuable discussions. M.L. acknowledges support from the Austrian Science Fund (FWF) under Project No. P29902-N27 and from the European Research Council (ERC) Starting Grant No. 801770 (ANGULON). G.B. acknowledges support from the Austrian Science Fund (FWF) under Project No. M2461-N27. A.D. acknowledges funding from the European Union’s Horizon 2020 research and innovation programme under the European Research Council (ERC) Grant Agreement No. 694227 and under the Marie Sklodowska-Curie Grant Agreement No. 836146. R.S. was supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC-2111 – 390814868. article_number: '164302' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Xiang full_name: Li, Xiang id: 4B7E523C-F248-11E8-B48F-1D18A9856A87 last_name: Li - first_name: Enderalp full_name: Yakaboylu, Enderalp id: 38CB71F6-F248-11E8-B48F-1D18A9856A87 last_name: Yakaboylu orcid: 0000-0001-5973-0874 - first_name: Giacomo full_name: Bighin, Giacomo id: 4CA96FD4-F248-11E8-B48F-1D18A9856A87 last_name: Bighin orcid: 0000-0001-8823-9777 - first_name: Richard full_name: Schmidt, Richard last_name: Schmidt - first_name: Mikhail full_name: Lemeshko, Mikhail id: 37CB05FA-F248-11E8-B48F-1D18A9856A87 last_name: Lemeshko orcid: 0000-0002-6990-7802 - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 citation: ama: Li X, Yakaboylu E, Bighin G, Schmidt R, Lemeshko M, Deuchert A. Intermolecular forces and correlations mediated by a phonon bath. The Journal of Chemical Physics. 2020;152(16). doi:10.1063/1.5144759 apa: Li, X., Yakaboylu, E., Bighin, G., Schmidt, R., Lemeshko, M., & Deuchert, A. (2020). Intermolecular forces and correlations mediated by a phonon bath. The Journal of Chemical Physics. AIP Publishing. https://doi.org/10.1063/1.5144759 chicago: Li, Xiang, Enderalp Yakaboylu, Giacomo Bighin, Richard Schmidt, Mikhail Lemeshko, and Andreas Deuchert. “Intermolecular Forces and Correlations Mediated by a Phonon Bath.” The Journal of Chemical Physics. AIP Publishing, 2020. https://doi.org/10.1063/1.5144759. ieee: X. Li, E. Yakaboylu, G. Bighin, R. Schmidt, M. Lemeshko, and A. Deuchert, “Intermolecular forces and correlations mediated by a phonon bath,” The Journal of Chemical Physics, vol. 152, no. 16. AIP Publishing, 2020. ista: Li X, Yakaboylu E, Bighin G, Schmidt R, Lemeshko M, Deuchert A. 2020. Intermolecular forces and correlations mediated by a phonon bath. The Journal of Chemical Physics. 152(16), 164302. mla: Li, Xiang, et al. “Intermolecular Forces and Correlations Mediated by a Phonon Bath.” The Journal of Chemical Physics, vol. 152, no. 16, 164302, AIP Publishing, 2020, doi:10.1063/1.5144759. short: X. Li, E. Yakaboylu, G. Bighin, R. Schmidt, M. Lemeshko, A. Deuchert, The Journal of Chemical Physics 152 (2020). date_created: 2020-09-30T10:33:17Z date_published: 2020-04-27T00:00:00Z date_updated: 2024-08-07T07:16:53Z day: '27' department: - _id: MiLe - _id: RoSe doi: 10.1063/1.5144759 ec_funded: 1 external_id: arxiv: - '1912.02658' isi: - '000530448300001' intvolume: ' 152' isi: 1 issue: '16' keyword: - Physical and Theoretical Chemistry - General Physics and Astronomy language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1912.02658 month: '04' oa: 1 oa_version: Preprint project: - _id: 26031614-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: P29902 name: Quantum rotations in the presence of a many-body environment - _id: 2688CF98-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '801770' name: 'Angulon: physics and applications of a new quasiparticle' - _id: 26986C82-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: M02641 name: A path-integral approach to composite impurities - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems publication: The Journal of Chemical Physics publication_identifier: eissn: - 1089-7690 issn: - 0021-9606 publication_status: published publisher: AIP Publishing quality_controlled: '1' related_material: record: - id: '8958' relation: dissertation_contains status: public status: public title: Intermolecular forces and correlations mediated by a phonon bath type: journal_article user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 volume: 152 year: '2020' ... --- _id: '7650' abstract: - lang: eng text: We consider a dilute, homogeneous Bose gas at positive temperature. The system is investigated in the Gross–Pitaevskii limit, where the scattering length a is so small that the interaction energy is of the same order of magnitude as the spectral gap of the Laplacian, and for temperatures that are comparable to the critical temperature of the ideal gas. We show that the difference between the specific free energy of the interacting system and the one of the ideal gas is to leading order given by 4πa(2ϱ2−ϱ20). Here ϱ denotes the density of the system and ϱ0 is the expected condensate density of the ideal gas. Additionally, we show that the one-particle density matrix of any approximate minimizer of the Gibbs free energy functional is to leading order given by the one of the ideal gas. This in particular proves Bose–Einstein condensation with critical temperature given by the one of the ideal gas to leading order. One key ingredient of our proof is a novel use of the Gibbs variational principle that goes hand in hand with the c-number substitution. acknowledgement: Open access funding provided by Institute of Science and Technology (IST Austria). It is a pleasure to thank Jakob Yngvason for helpful discussions. Financial support by the European Research Council (ERC) under the European Union’sHorizon 2020 research and innovation programme (Grant Agreement No. 694227) is gratefully acknowledged. A. D. acknowledges funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 836146. article_processing_charge: Yes (via OA deal) article_type: original arxiv: 1 author: - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 - first_name: Robert full_name: Seiringer, Robert id: 4AFD0470-F248-11E8-B48F-1D18A9856A87 last_name: Seiringer orcid: 0000-0002-6781-0521 citation: ama: Deuchert A, Seiringer R. Gross-Pitaevskii limit of a homogeneous Bose gas at positive temperature. Archive for Rational Mechanics and Analysis. 2020;236(6):1217-1271. doi:10.1007/s00205-020-01489-4 apa: Deuchert, A., & Seiringer, R. (2020). Gross-Pitaevskii limit of a homogeneous Bose gas at positive temperature. Archive for Rational Mechanics and Analysis. Springer Nature. https://doi.org/10.1007/s00205-020-01489-4 chicago: Deuchert, Andreas, and Robert Seiringer. “Gross-Pitaevskii Limit of a Homogeneous Bose Gas at Positive Temperature.” Archive for Rational Mechanics and Analysis. Springer Nature, 2020. https://doi.org/10.1007/s00205-020-01489-4. ieee: A. Deuchert and R. Seiringer, “Gross-Pitaevskii limit of a homogeneous Bose gas at positive temperature,” Archive for Rational Mechanics and Analysis, vol. 236, no. 6. Springer Nature, pp. 1217–1271, 2020. ista: Deuchert A, Seiringer R. 2020. Gross-Pitaevskii limit of a homogeneous Bose gas at positive temperature. Archive for Rational Mechanics and Analysis. 236(6), 1217–1271. mla: Deuchert, Andreas, and Robert Seiringer. “Gross-Pitaevskii Limit of a Homogeneous Bose Gas at Positive Temperature.” Archive for Rational Mechanics and Analysis, vol. 236, no. 6, Springer Nature, 2020, pp. 1217–71, doi:10.1007/s00205-020-01489-4. short: A. Deuchert, R. Seiringer, Archive for Rational Mechanics and Analysis 236 (2020) 1217–1271. date_created: 2020-04-08T15:18:03Z date_published: 2020-03-09T00:00:00Z date_updated: 2023-09-05T14:18:49Z day: '09' ddc: - '510' department: - _id: RoSe doi: 10.1007/s00205-020-01489-4 ec_funded: 1 external_id: arxiv: - '1901.11363' isi: - '000519415000001' file: - access_level: open_access checksum: b645fb64bfe95bbc05b3eea374109a9c content_type: application/pdf creator: dernst date_created: 2020-11-20T13:17:42Z date_updated: 2020-11-20T13:17:42Z file_id: '8785' file_name: 2020_ArchRatMechanicsAnalysis_Deuchert.pdf file_size: 704633 relation: main_file success: 1 file_date_updated: 2020-11-20T13:17:42Z has_accepted_license: '1' intvolume: ' 236' isi: 1 issue: '6' language: - iso: eng month: '03' oa: 1 oa_version: Published Version page: 1217-1271 project: - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems - _id: B67AFEDC-15C9-11EA-A837-991A96BB2854 name: IST Austria Open Access Fund publication: Archive for Rational Mechanics and Analysis publication_identifier: eissn: - 1432-0673 issn: - 0003-9527 publication_status: published publisher: Springer Nature quality_controlled: '1' scopus_import: '1' status: public title: Gross-Pitaevskii limit of a homogeneous Bose gas at positive temperature tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 volume: 236 year: '2020' ... --- _id: '80' abstract: - lang: eng text: 'We consider an interacting, dilute Bose gas trapped in a harmonic potential at a positive temperature. The system is analyzed in a combination of a thermodynamic and a Gross–Pitaevskii (GP) limit where the trap frequency ω, the temperature T, and the particle number N are related by N∼ (T/ ω) 3→ ∞ while the scattering length is so small that the interaction energy per particle around the center of the trap is of the same order of magnitude as the spectral gap in the trap. We prove that the difference between the canonical free energy of the interacting gas and the one of the noninteracting system can be obtained by minimizing the GP energy functional. We also prove Bose–Einstein condensation in the following sense: The one-particle density matrix of any approximate minimizer of the canonical free energy functional is to leading order given by that of the noninteracting gas but with the free condensate wavefunction replaced by the GP minimizer.' article_processing_charge: Yes (via OA deal) article_type: original author: - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 - first_name: Robert full_name: Seiringer, Robert id: 4AFD0470-F248-11E8-B48F-1D18A9856A87 last_name: Seiringer orcid: 0000-0002-6781-0521 - first_name: Jakob full_name: Yngvason, Jakob last_name: Yngvason citation: ama: Deuchert A, Seiringer R, Yngvason J. Bose–Einstein condensation in a dilute, trapped gas at positive temperature. Communications in Mathematical Physics. 2019;368(2):723-776. doi:10.1007/s00220-018-3239-0 apa: Deuchert, A., Seiringer, R., & Yngvason, J. (2019). Bose–Einstein condensation in a dilute, trapped gas at positive temperature. Communications in Mathematical Physics. Springer. https://doi.org/10.1007/s00220-018-3239-0 chicago: Deuchert, Andreas, Robert Seiringer, and Jakob Yngvason. “Bose–Einstein Condensation in a Dilute, Trapped Gas at Positive Temperature.” Communications in Mathematical Physics. Springer, 2019. https://doi.org/10.1007/s00220-018-3239-0. ieee: A. Deuchert, R. Seiringer, and J. Yngvason, “Bose–Einstein condensation in a dilute, trapped gas at positive temperature,” Communications in Mathematical Physics, vol. 368, no. 2. Springer, pp. 723–776, 2019. ista: Deuchert A, Seiringer R, Yngvason J. 2019. Bose–Einstein condensation in a dilute, trapped gas at positive temperature. Communications in Mathematical Physics. 368(2), 723–776. mla: Deuchert, Andreas, et al. “Bose–Einstein Condensation in a Dilute, Trapped Gas at Positive Temperature.” Communications in Mathematical Physics, vol. 368, no. 2, Springer, 2019, pp. 723–76, doi:10.1007/s00220-018-3239-0. short: A. Deuchert, R. Seiringer, J. Yngvason, Communications in Mathematical Physics 368 (2019) 723–776. date_created: 2018-12-11T11:44:31Z date_published: 2019-06-01T00:00:00Z date_updated: 2023-08-24T14:27:51Z day: '01' ddc: - '530' department: - _id: RoSe doi: 10.1007/s00220-018-3239-0 ec_funded: 1 external_id: isi: - '000467796800007' file: - access_level: open_access checksum: c7e9880b43ac726712c1365e9f2f73a6 content_type: application/pdf creator: dernst date_created: 2018-12-17T10:34:06Z date_updated: 2020-07-14T12:48:07Z file_id: '5688' file_name: 2018_CommunMathPhys_Deuchert.pdf file_size: 893902 relation: main_file file_date_updated: 2020-07-14T12:48:07Z has_accepted_license: '1' intvolume: ' 368' isi: 1 issue: '2' language: - iso: eng month: '06' oa: 1 oa_version: Published Version page: 723-776 project: - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems - _id: 25C878CE-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: P27533_N27 name: Structure of the Excitation Spectrum for Many-Body Quantum Systems publication: Communications in Mathematical Physics publication_status: published publisher: Springer publist_id: '7974' quality_controlled: '1' scopus_import: '1' status: public title: Bose–Einstein condensation in a dilute, trapped gas at positive temperature tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 368 year: '2019' ... --- _id: '7524' abstract: - lang: eng text: "We prove a lower bound for the free energy (per unit volume) of the two-dimensional Bose gas in the thermodynamic limit. We show that the free energy at density $\\rho$ and inverse temperature $\\beta$ differs from the one of the non-interacting system by the correction term $4 \\pi \\rho^2 |\\ln a^2 \\rho|^{-1} (2 - [1 - \\beta_{\\mathrm{c}}/\\beta]_+^2)$. Here $a$ is the scattering length of the interaction potential, $[\\cdot]_+ = \\max\\{ 0, \\cdot \\}$ and $\\beta_{\\mathrm{c}}$ is the inverse Berezinskii--Kosterlitz--Thouless critical temperature for superfluidity. The result is valid in the dilute limit\r\n$a^2\\rho \\ll 1$ and if $\\beta \\rho \\gtrsim 1$." article_processing_charge: No author: - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 - first_name: Simon full_name: Mayer, Simon id: 30C4630A-F248-11E8-B48F-1D18A9856A87 last_name: Mayer - first_name: Robert full_name: Seiringer, Robert id: 4AFD0470-F248-11E8-B48F-1D18A9856A87 last_name: Seiringer orcid: 0000-0002-6781-0521 citation: ama: Deuchert A, Mayer S, Seiringer R. The free energy of the two-dimensional dilute Bose gas. I. Lower bound. arXiv:191003372. apa: Deuchert, A., Mayer, S., & Seiringer, R. (n.d.). The free energy of the two-dimensional dilute Bose gas. I. Lower bound. arXiv:1910.03372. ArXiv. chicago: Deuchert, Andreas, Simon Mayer, and Robert Seiringer. “The Free Energy of the Two-Dimensional Dilute Bose Gas. I. Lower Bound.” ArXiv:1910.03372. ArXiv, n.d. ieee: A. Deuchert, S. Mayer, and R. Seiringer, “The free energy of the two-dimensional dilute Bose gas. I. Lower bound,” arXiv:1910.03372. ArXiv. ista: Deuchert A, Mayer S, Seiringer R. The free energy of the two-dimensional dilute Bose gas. I. Lower bound. arXiv:1910.03372, . mla: Deuchert, Andreas, et al. “The Free Energy of the Two-Dimensional Dilute Bose Gas. I. Lower Bound.” ArXiv:1910.03372, ArXiv. short: A. Deuchert, S. Mayer, R. Seiringer, ArXiv:1910.03372 (n.d.). date_created: 2020-02-26T08:46:40Z date_published: 2019-10-08T00:00:00Z date_updated: 2023-09-07T13:12:41Z day: '08' department: - _id: RoSe ec_funded: 1 language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1910.03372 month: '10' oa: 1 oa_version: Preprint page: '61' project: - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems publication: arXiv:1910.03372 publication_status: draft publisher: ArXiv related_material: record: - id: '7790' relation: later_version status: public - id: '7514' relation: dissertation_contains status: public scopus_import: 1 status: public title: The free energy of the two-dimensional dilute Bose gas. I. Lower bound type: preprint user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2019' ... --- _id: '5983' abstract: - lang: eng text: We study a quantum impurity possessing both translational and internal rotational degrees of freedom interacting with a bosonic bath. Such a system corresponds to a “rotating polaron,” which can be used to model, e.g., a rotating molecule immersed in an ultracold Bose gas or superfluid helium. We derive the Hamiltonian of the rotating polaron and study its spectrum in the weak- and strong-coupling regimes using a combination of variational, diagrammatic, and mean-field approaches. We reveal how the coupling between linear and angular momenta affects stable quasiparticle states, and demonstrate that internal rotation leads to an enhanced self-localization in the translational degrees of freedom. article_number: '224506' article_processing_charge: No arxiv: 1 author: - first_name: Enderalp full_name: Yakaboylu, Enderalp id: 38CB71F6-F248-11E8-B48F-1D18A9856A87 last_name: Yakaboylu orcid: 0000-0001-5973-0874 - first_name: Bikashkali full_name: Midya, Bikashkali id: 456187FC-F248-11E8-B48F-1D18A9856A87 last_name: Midya - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 - first_name: Nikolai K full_name: Leopold, Nikolai K id: 4BC40BEC-F248-11E8-B48F-1D18A9856A87 last_name: Leopold orcid: 0000-0002-0495-6822 - first_name: Mikhail full_name: Lemeshko, Mikhail id: 37CB05FA-F248-11E8-B48F-1D18A9856A87 last_name: Lemeshko orcid: 0000-0002-6990-7802 citation: ama: 'Yakaboylu E, Midya B, Deuchert A, Leopold NK, Lemeshko M. Theory of the rotating polaron: Spectrum and self-localization. Physical Review B. 2018;98(22). doi:10.1103/physrevb.98.224506' apa: 'Yakaboylu, E., Midya, B., Deuchert, A., Leopold, N. K., & Lemeshko, M. (2018). Theory of the rotating polaron: Spectrum and self-localization. Physical Review B. American Physical Society. https://doi.org/10.1103/physrevb.98.224506' chicago: 'Yakaboylu, Enderalp, Bikashkali Midya, Andreas Deuchert, Nikolai K Leopold, and Mikhail Lemeshko. “Theory of the Rotating Polaron: Spectrum and Self-Localization.” Physical Review B. American Physical Society, 2018. https://doi.org/10.1103/physrevb.98.224506.' ieee: 'E. Yakaboylu, B. Midya, A. Deuchert, N. K. Leopold, and M. Lemeshko, “Theory of the rotating polaron: Spectrum and self-localization,” Physical Review B, vol. 98, no. 22. American Physical Society, 2018.' ista: 'Yakaboylu E, Midya B, Deuchert A, Leopold NK, Lemeshko M. 2018. Theory of the rotating polaron: Spectrum and self-localization. Physical Review B. 98(22), 224506.' mla: 'Yakaboylu, Enderalp, et al. “Theory of the Rotating Polaron: Spectrum and Self-Localization.” Physical Review B, vol. 98, no. 22, 224506, American Physical Society, 2018, doi:10.1103/physrevb.98.224506.' short: E. Yakaboylu, B. Midya, A. Deuchert, N.K. Leopold, M. Lemeshko, Physical Review B 98 (2018). date_created: 2019-02-14T10:37:09Z date_published: 2018-12-12T00:00:00Z date_updated: 2023-09-19T14:29:03Z day: '12' department: - _id: MiLe - _id: RoSe doi: 10.1103/physrevb.98.224506 ec_funded: 1 external_id: arxiv: - '1809.01204' isi: - '000452992700008' intvolume: ' 98' isi: 1 issue: '22' language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1809.01204 month: '12' oa: 1 oa_version: Preprint project: - _id: 25681D80-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '291734' name: International IST Postdoc Fellowship Programme - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems publication: Physical Review B publication_identifier: eissn: - 2469-9969 issn: - 2469-9950 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: 'Theory of the rotating polaron: Spectrum and self-localization' type: journal_article user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 volume: 98 year: '2018' ... --- _id: '400' abstract: - lang: eng text: We consider the two-dimensional BCS functional with a radial pair interaction. We show that the translational symmetry is not broken in a certain temperature interval below the critical temperature. In the case of vanishing angular momentum, our results carry over to the three-dimensional case. article_processing_charge: Yes (via OA deal) author: - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 - first_name: Alissa full_name: Geisinge, Alissa last_name: Geisinge - first_name: Christian full_name: Hainzl, Christian last_name: Hainzl - first_name: Michael full_name: Loss, Michael last_name: Loss citation: ama: Deuchert A, Geisinge A, Hainzl C, Loss M. Persistence of translational symmetry in the BCS model with radial pair interaction. Annales Henri Poincare. 2018;19(5):1507-1527. doi:10.1007/s00023-018-0665-7 apa: Deuchert, A., Geisinge, A., Hainzl, C., & Loss, M. (2018). Persistence of translational symmetry in the BCS model with radial pair interaction. Annales Henri Poincare. Springer. https://doi.org/10.1007/s00023-018-0665-7 chicago: Deuchert, Andreas, Alissa Geisinge, Christian Hainzl, and Michael Loss. “Persistence of Translational Symmetry in the BCS Model with Radial Pair Interaction.” Annales Henri Poincare. Springer, 2018. https://doi.org/10.1007/s00023-018-0665-7. ieee: A. Deuchert, A. Geisinge, C. Hainzl, and M. Loss, “Persistence of translational symmetry in the BCS model with radial pair interaction,” Annales Henri Poincare, vol. 19, no. 5. Springer, pp. 1507–1527, 2018. ista: Deuchert A, Geisinge A, Hainzl C, Loss M. 2018. Persistence of translational symmetry in the BCS model with radial pair interaction. Annales Henri Poincare. 19(5), 1507–1527. mla: Deuchert, Andreas, et al. “Persistence of Translational Symmetry in the BCS Model with Radial Pair Interaction.” Annales Henri Poincare, vol. 19, no. 5, Springer, 2018, pp. 1507–27, doi:10.1007/s00023-018-0665-7. short: A. Deuchert, A. Geisinge, C. Hainzl, M. Loss, Annales Henri Poincare 19 (2018) 1507–1527. date_created: 2018-12-11T11:46:15Z date_published: 2018-05-01T00:00:00Z date_updated: 2023-09-15T12:04:15Z day: '01' ddc: - '510' department: - _id: RoSe doi: 10.1007/s00023-018-0665-7 ec_funded: 1 external_id: isi: - '000429799900008' file: - access_level: open_access checksum: 04d2c9bd7cbf3ca1d7acaaf4e7dca3e5 content_type: application/pdf creator: system date_created: 2018-12-12T10:12:47Z date_updated: 2020-07-14T12:46:22Z file_id: '4966' file_name: IST-2018-1011-v1+1_2018_Deuchert_Persistence.pdf file_size: 582680 relation: main_file file_date_updated: 2020-07-14T12:46:22Z has_accepted_license: '1' intvolume: ' 19' isi: 1 issue: '5' language: - iso: eng month: '05' oa: 1 oa_version: Published Version page: 1507 - 1527 project: - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems - _id: B67AFEDC-15C9-11EA-A837-991A96BB2854 name: IST Austria Open Access Fund publication: Annales Henri Poincare publication_status: published publisher: Springer publist_id: '7429' pubrep_id: '1011' quality_controlled: '1' scopus_import: '1' status: public title: Persistence of translational symmetry in the BCS model with radial pair interaction tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 volume: 19 year: '2018' ... --- _id: '912' abstract: - lang: eng text: "We consider a many-body system of fermionic atoms interacting via a local pair potential and subject to an external potential within the framework of Bardeen-Cooper-Schrieffer (BCS) theory. We measure the free energy of the whole sample with respect to the free energy of a reference state which allows us to define a BCS functional with boundary conditions at infinity. Our main result is a lower bound for this energy functional in terms of expressions that typically appear in Ginzburg-Landau functionals.\r\n" article_number: '081901' article_processing_charge: No author: - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 citation: ama: Deuchert A. A lower bound for the BCS functional with boundary conditions at infinity. Journal of Mathematical Physics. 2017;58(8). doi:10.1063/1.4996580 apa: Deuchert, A. (2017). A lower bound for the BCS functional with boundary conditions at infinity. Journal of Mathematical Physics. AIP Publishing. https://doi.org/10.1063/1.4996580 chicago: Deuchert, Andreas. “A Lower Bound for the BCS Functional with Boundary Conditions at Infinity.” Journal of Mathematical Physics. AIP Publishing, 2017. https://doi.org/10.1063/1.4996580. ieee: A. Deuchert, “A lower bound for the BCS functional with boundary conditions at infinity,” Journal of Mathematical Physics, vol. 58, no. 8. AIP Publishing, 2017. ista: Deuchert A. 2017. A lower bound for the BCS functional with boundary conditions at infinity. Journal of Mathematical Physics. 58(8), 081901. mla: Deuchert, Andreas. “A Lower Bound for the BCS Functional with Boundary Conditions at Infinity.” Journal of Mathematical Physics, vol. 58, no. 8, 081901, AIP Publishing, 2017, doi:10.1063/1.4996580. short: A. Deuchert, Journal of Mathematical Physics 58 (2017). date_created: 2018-12-11T11:49:10Z date_published: 2017-08-01T00:00:00Z date_updated: 2024-02-28T13:07:56Z day: '01' department: - _id: RoSe doi: 10.1063/1.4996580 ec_funded: 1 external_id: isi: - '000409197200015' intvolume: ' 58' isi: 1 issue: '8' language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1703.04616 month: '08' oa: 1 oa_version: Submitted Version project: - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems publication: ' Journal of Mathematical Physics' publication_identifier: issn: - '00222488' publication_status: published publisher: AIP Publishing publist_id: '6531' quality_controlled: '1' scopus_import: '1' status: public title: A lower bound for the BCS functional with boundary conditions at infinity type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 58 year: '2017' ... --- _id: '997' abstract: - lang: eng text: Recently it was shown that molecules rotating in superfluid helium can be described in terms of the angulon quasiparticles (Phys. Rev. Lett. 118, 095301 (2017)). Here we demonstrate that in the experimentally realized regime the angulon can be seen as a point charge on a 2-sphere interacting with a gauge field of a non-abelian magnetic monopole. Unlike in several other settings, the gauge fields of the angulon problem emerge in the real coordinate space, as opposed to the momentum space or some effective parameter space. Furthermore, we find a topological transition associated with making the monopole abelian, which takes place in the vicinity of the previously reported angulon instabilities. These results pave the way for studying topological phenomena in experiments on molecules trapped in superfluid helium nanodroplets, as well as on other realizations of orbital impurity problems. article_number: '235301' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Enderalp full_name: Yakaboylu, Enderalp id: 38CB71F6-F248-11E8-B48F-1D18A9856A87 last_name: Yakaboylu orcid: 0000-0001-5973-0874 - first_name: Andreas full_name: Deuchert, Andreas id: 4DA65CD0-F248-11E8-B48F-1D18A9856A87 last_name: Deuchert orcid: 0000-0003-3146-6746 - first_name: Mikhail full_name: Lemeshko, Mikhail id: 37CB05FA-F248-11E8-B48F-1D18A9856A87 last_name: Lemeshko orcid: 0000-0002-6990-7802 citation: ama: Yakaboylu E, Deuchert A, Lemeshko M. Emergence of non-abelian magnetic monopoles in a quantum impurity problem. Physical Review Letters. 2017;119(23). doi:10.1103/PhysRevLett.119.235301 apa: Yakaboylu, E., Deuchert, A., & Lemeshko, M. (2017). Emergence of non-abelian magnetic monopoles in a quantum impurity problem. Physical Review Letters. American Physical Society. https://doi.org/10.1103/PhysRevLett.119.235301 chicago: Yakaboylu, Enderalp, Andreas Deuchert, and Mikhail Lemeshko. “Emergence of Non-Abelian Magnetic Monopoles in a Quantum Impurity Problem.” Physical Review Letters. American Physical Society, 2017. https://doi.org/10.1103/PhysRevLett.119.235301. ieee: E. Yakaboylu, A. Deuchert, and M. Lemeshko, “Emergence of non-abelian magnetic monopoles in a quantum impurity problem,” Physical Review Letters, vol. 119, no. 23. American Physical Society, 2017. ista: Yakaboylu E, Deuchert A, Lemeshko M. 2017. Emergence of non-abelian magnetic monopoles in a quantum impurity problem. Physical Review Letters. 119(23), 235301. mla: Yakaboylu, Enderalp, et al. “Emergence of Non-Abelian Magnetic Monopoles in a Quantum Impurity Problem.” Physical Review Letters, vol. 119, no. 23, 235301, American Physical Society, 2017, doi:10.1103/PhysRevLett.119.235301. short: E. Yakaboylu, A. Deuchert, M. Lemeshko, Physical Review Letters 119 (2017). date_created: 2018-12-11T11:49:36Z date_published: 2017-12-06T00:00:00Z date_updated: 2023-10-10T13:31:54Z day: '06' department: - _id: MiLe - _id: RoSe doi: 10.1103/PhysRevLett.119.235301 ec_funded: 1 external_id: arxiv: - '1705.05162' isi: - '000417132100007' intvolume: ' 119' isi: 1 issue: '23' language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1705.05162 month: '12' oa: 1 oa_version: Preprint project: - _id: 25681D80-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '291734' name: International IST Postdoc Fellowship Programme - _id: 25C6DC12-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '694227' name: Analysis of quantum many-body systems - _id: 26031614-B435-11E9-9278-68D0E5697425 call_identifier: FWF grant_number: P29902 name: Quantum rotations in the presence of a many-body environment publication: Physical Review Letters publication_identifier: issn: - 0031-9007 publication_status: published publisher: American Physical Society publist_id: '6401' quality_controlled: '1' scopus_import: '1' status: public title: Emergence of non-abelian magnetic monopoles in a quantum impurity problem type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 119 year: '2017' ...