--- _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 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: '6002' abstract: - lang: eng text: The Bogoliubov free energy functional is analysed. The functional serves as a model of a translation-invariant Bose gas at positive temperature. We prove the existence of minimizers in the case of repulsive interactions given by a sufficiently regular two-body potential. Furthermore, we prove the existence of a phase transition in this model and provide its phase diagram. article_processing_charge: No author: - first_name: Marcin M full_name: Napiórkowski, Marcin M id: 4197AD04-F248-11E8-B48F-1D18A9856A87 last_name: Napiórkowski - first_name: Robin full_name: Reuvers, Robin last_name: Reuvers - first_name: Jan Philip full_name: Solovej, Jan Philip last_name: Solovej citation: ama: 'Napiórkowski MM, Reuvers R, Solovej JP. The Bogoliubov free energy functional I: Existence of minimizers and phase diagram. Archive for Rational Mechanics and Analysis. 2018;229(3):1037-1090. doi:10.1007/s00205-018-1232-6' apa: 'Napiórkowski, M. M., Reuvers, R., & Solovej, J. P. (2018). The Bogoliubov free energy functional I: Existence of minimizers and phase diagram. Archive for Rational Mechanics and Analysis. Springer Nature. https://doi.org/10.1007/s00205-018-1232-6' chicago: 'Napiórkowski, Marcin M, Robin Reuvers, and Jan Philip Solovej. “The Bogoliubov Free Energy Functional I: Existence of Minimizers and Phase Diagram.” Archive for Rational Mechanics and Analysis. Springer Nature, 2018. https://doi.org/10.1007/s00205-018-1232-6.' ieee: 'M. M. Napiórkowski, R. Reuvers, and J. P. Solovej, “The Bogoliubov free energy functional I: Existence of minimizers and phase diagram,” Archive for Rational Mechanics and Analysis, vol. 229, no. 3. Springer Nature, pp. 1037–1090, 2018.' ista: 'Napiórkowski MM, Reuvers R, Solovej JP. 2018. The Bogoliubov free energy functional I: Existence of minimizers and phase diagram. Archive for Rational Mechanics and Analysis. 229(3), 1037–1090.' mla: 'Napiórkowski, Marcin M., et al. “The Bogoliubov Free Energy Functional I: Existence of Minimizers and Phase Diagram.” Archive for Rational Mechanics and Analysis, vol. 229, no. 3, Springer Nature, 2018, pp. 1037–90, doi:10.1007/s00205-018-1232-6.' short: M.M. Napiórkowski, R. Reuvers, J.P. Solovej, Archive for Rational Mechanics and Analysis 229 (2018) 1037–1090. date_created: 2019-02-14T13:40:53Z date_published: 2018-09-01T00:00:00Z date_updated: 2023-09-19T14:33:12Z day: '01' department: - _id: RoSe doi: 10.1007/s00205-018-1232-6 external_id: arxiv: - '1511.05935' isi: - '000435367300003' intvolume: ' 229' isi: 1 issue: '3' language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1511.05935 month: '09' oa: 1 oa_version: Preprint page: 1037-1090 project: - _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: 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: 'The Bogoliubov free energy functional I: Existence of minimizers and phase diagram' type: journal_article user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 volume: 229 year: '2018' ... --- _id: '52' abstract: - lang: eng text: In this thesis we will discuss systems of point interacting fermions, their stability and other spectral properties. Whereas for bosons a point interacting system is always unstable this ques- tion is more subtle for a gas of two species of fermions. In particular the answer depends on the mass ratio between these two species. Most of this work will be focused on the N + M model which consists of two species of fermions with N, M particles respectively which interact via point interactions. We will introduce this model using a formal limit and discuss the N + 1 system in more detail. In particular, we will show that for mass ratios above a critical one, which does not depend on the particle number, the N + 1 system is stable. In the context of this model we will prove rigorous versions of Tan relations which relate various quantities of the point-interacting model. By restricting the N + 1 system to a box we define a finite density model with point in- teractions. In the context of this system we will discuss the energy change when introducing a point-interacting impurity into a system of non-interacting fermions. We will see that this change in energy is bounded independently of the particle number and in particular the bound only depends on the density and the scattering length. As another special case of the N + M model we will show stability of the 2 + 2 model for mass ratios in an interval around one. Further we will investigate a different model of point interactions which was discussed before in the literature and which is, contrary to the N + M model, not given by a limiting procedure but is based on a Dirichlet form. We will show that this system behaves trivially in the thermodynamic limit, i.e. the free energy per particle is the same as the one of the non-interacting system. alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Thomas full_name: Moser, Thomas id: 2B5FC9A4-F248-11E8-B48F-1D18A9856A87 last_name: Moser citation: ama: Moser T. Point interactions in systems of fermions. 2018. doi:10.15479/AT:ISTA:th_1043 apa: Moser, T. (2018). Point interactions in systems of fermions. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:th_1043 chicago: Moser, Thomas. “Point Interactions in Systems of Fermions.” Institute of Science and Technology Austria, 2018. https://doi.org/10.15479/AT:ISTA:th_1043. ieee: T. Moser, “Point interactions in systems of fermions,” Institute of Science and Technology Austria, 2018. ista: Moser T. 2018. Point interactions in systems of fermions. Institute of Science and Technology Austria. mla: Moser, Thomas. Point Interactions in Systems of Fermions. Institute of Science and Technology Austria, 2018, doi:10.15479/AT:ISTA:th_1043. short: T. Moser, Point Interactions in Systems of Fermions, Institute of Science and Technology Austria, 2018. date_created: 2018-12-11T11:44:22Z date_published: 2018-09-04T00:00:00Z date_updated: 2023-09-27T12:34:14Z day: '04' ddc: - '515' - '530' - '519' degree_awarded: PhD department: - _id: RoSe doi: 10.15479/AT:ISTA:th_1043 file: - access_level: open_access checksum: fbd8c747d148b468a21213b7cf175225 content_type: application/pdf creator: dernst date_created: 2019-04-09T07:45:38Z date_updated: 2020-07-14T12:46:37Z file_id: '6256' file_name: 2018_Thesis_Moser.pdf file_size: 851164 relation: main_file - access_level: closed checksum: c28e16ecfc1126d3ce324ec96493c01e content_type: application/zip creator: dernst date_created: 2019-04-09T07:45:38Z date_updated: 2020-07-14T12:46:37Z file_id: '6257' file_name: 2018_Thesis_Moser_Source.zip file_size: 1531516 relation: source_file file_date_updated: 2020-07-14T12:46:37Z has_accepted_license: '1' language: - iso: eng month: '09' oa: 1 oa_version: Published Version page: '115' project: - _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_identifier: issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria publist_id: '8002' pubrep_id: '1043' related_material: record: - id: '5856' relation: part_of_dissertation status: public - id: '154' relation: part_of_dissertation status: public - id: '1198' relation: part_of_dissertation status: public - id: '741' relation: part_of_dissertation status: public status: public supervisor: - first_name: Robert full_name: Seiringer, Robert id: 4AFD0470-F248-11E8-B48F-1D18A9856A87 last_name: Seiringer orcid: 0000-0002-6781-0521 title: Point interactions in systems of fermions type: dissertation user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1 year: '2018' ... --- _id: '180' abstract: - lang: eng text: In this paper we define and study the classical Uniform Electron Gas (UEG), a system of infinitely many electrons whose density is constant everywhere in space. The UEG is defined differently from Jellium, which has a positive constant background but no constraint on the density. We prove that the UEG arises in Density Functional Theory in the limit of a slowly varying density, minimizing the indirect Coulomb energy. We also construct the quantum UEG and compare it to the classical UEG at low density. acknowledgement: "This project has received funding from the European Research Council (ERC) under the European\r\nUnion’s Horizon 2020 research and innovation programme (grant agreement 694227 for R.S. and MDFT 725528 for M.L.). Financial support by the Austrian Science Fund (FWF), project No P 27533-N27 (R.S.) and by the US National Science Foundation, grant No PHY12-1265118 (E.H.L.) are gratefully acknowledged." article_processing_charge: No article_type: original author: - first_name: Mathieu full_name: Lewi, Mathieu last_name: Lewi - first_name: Élliott full_name: Lieb, Élliott last_name: Lieb - first_name: Robert full_name: Seiringer, Robert id: 4AFD0470-F248-11E8-B48F-1D18A9856A87 last_name: Seiringer orcid: 0000-0002-6781-0521 citation: ama: Lewi M, Lieb É, Seiringer R. Statistical mechanics of the uniform electron gas. Journal de l’Ecole Polytechnique - Mathematiques. 2018;5:79-116. doi:10.5802/jep.64 apa: Lewi, M., Lieb, É., & Seiringer, R. (2018). Statistical mechanics of the uniform electron gas. Journal de l’Ecole Polytechnique - Mathematiques. Ecole Polytechnique. https://doi.org/10.5802/jep.64 chicago: Lewi, Mathieu, Élliott Lieb, and Robert Seiringer. “Statistical Mechanics of the Uniform Electron Gas.” Journal de l’Ecole Polytechnique - Mathematiques. Ecole Polytechnique, 2018. https://doi.org/10.5802/jep.64. ieee: M. Lewi, É. Lieb, and R. Seiringer, “Statistical mechanics of the uniform electron gas,” Journal de l’Ecole Polytechnique - Mathematiques, vol. 5. Ecole Polytechnique, pp. 79–116, 2018. ista: Lewi M, Lieb É, Seiringer R. 2018. Statistical mechanics of the uniform electron gas. Journal de l’Ecole Polytechnique - Mathematiques. 5, 79–116. mla: Lewi, Mathieu, et al. “Statistical Mechanics of the Uniform Electron Gas.” Journal de l’Ecole Polytechnique - Mathematiques, vol. 5, Ecole Polytechnique, 2018, pp. 79–116, doi:10.5802/jep.64. short: M. Lewi, É. Lieb, R. Seiringer, Journal de l’Ecole Polytechnique - Mathematiques 5 (2018) 79–116. date_created: 2018-12-11T11:45:03Z date_published: 2018-07-01T00:00:00Z date_updated: 2023-10-17T08:05:28Z day: '01' ddc: - '510' department: - _id: RoSe doi: 10.5802/jep.64 ec_funded: 1 external_id: arxiv: - '1705.10676' file: - access_level: open_access checksum: 1ba7cccdf3900f42c4f715ae75d6813c content_type: application/pdf creator: dernst date_created: 2018-12-17T16:38:18Z date_updated: 2020-07-14T12:45:16Z file_id: '5726' file_name: 2018_JournaldeLecoleMath_Lewi.pdf file_size: 843938 relation: main_file file_date_updated: 2020-07-14T12:45:16Z has_accepted_license: '1' intvolume: ' 5' language: - iso: eng license: https://creativecommons.org/licenses/by-nd/4.0/ month: '07' oa: 1 oa_version: Published Version page: 79 - 116 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: Journal de l'Ecole Polytechnique - Mathematiques publication_identifier: eissn: - 2270-518X issn: - 2429-7100 publication_status: published publisher: Ecole Polytechnique publist_id: '7741' quality_controlled: '1' scopus_import: '1' status: public title: Statistical mechanics of the uniform electron gas tmp: image: /image/cc_by_nd.png legal_code_url: https://creativecommons.org/licenses/by-nd/4.0/legalcode name: Creative Commons Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0) short: CC BY-ND (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 5 year: '2018' ... --- _id: '484' abstract: - lang: eng text: We consider the dynamics of a large quantum system of N identical bosons in 3D interacting via a two-body potential of the form N3β-1w(Nβ(x - y)). For fixed 0 = β < 1/3 and large N, we obtain a norm approximation to the many-body evolution in the Nparticle Hilbert space. The leading order behaviour of the dynamics is determined by Hartree theory while the second order is given by Bogoliubov theory. author: - first_name: Phan full_name: Nam, Phan id: 404092F4-F248-11E8-B48F-1D18A9856A87 last_name: Nam - first_name: Marcin M full_name: Napiórkowski, Marcin M id: 4197AD04-F248-11E8-B48F-1D18A9856A87 last_name: Napiórkowski citation: ama: Nam P, Napiórkowski MM. Bogoliubov correction to the mean-field dynamics of interacting bosons. Advances in Theoretical and Mathematical Physics. 2017;21(3):683-738. doi:10.4310/ATMP.2017.v21.n3.a4 apa: Nam, P., & Napiórkowski, M. M. (2017). Bogoliubov correction to the mean-field dynamics of interacting bosons. Advances in Theoretical and Mathematical Physics. International Press. https://doi.org/10.4310/ATMP.2017.v21.n3.a4 chicago: Nam, Phan, and Marcin M Napiórkowski. “Bogoliubov Correction to the Mean-Field Dynamics of Interacting Bosons.” Advances in Theoretical and Mathematical Physics. International Press, 2017. https://doi.org/10.4310/ATMP.2017.v21.n3.a4. ieee: P. Nam and M. M. Napiórkowski, “Bogoliubov correction to the mean-field dynamics of interacting bosons,” Advances in Theoretical and Mathematical Physics, vol. 21, no. 3. International Press, pp. 683–738, 2017. ista: Nam P, Napiórkowski MM. 2017. Bogoliubov correction to the mean-field dynamics of interacting bosons. Advances in Theoretical and Mathematical Physics. 21(3), 683–738. mla: Nam, Phan, and Marcin M. Napiórkowski. “Bogoliubov Correction to the Mean-Field Dynamics of Interacting Bosons.” Advances in Theoretical and Mathematical Physics, vol. 21, no. 3, International Press, 2017, pp. 683–738, doi:10.4310/ATMP.2017.v21.n3.a4. short: P. Nam, M.M. Napiórkowski, Advances in Theoretical and Mathematical Physics 21 (2017) 683–738. date_created: 2018-12-11T11:46:43Z date_published: 2017-01-01T00:00:00Z date_updated: 2021-01-12T08:00:58Z day: '01' department: - _id: RoSe doi: 10.4310/ATMP.2017.v21.n3.a4 ec_funded: 1 intvolume: ' 21' issue: '3' language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1509.04631 month: '01' oa: 1 oa_version: Submitted Version page: 683 - 738 project: - _id: 25681D80-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '291734' name: International IST Postdoc Fellowship Programme - _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: Advances in Theoretical and Mathematical Physics publication_identifier: issn: - '10950761' publication_status: published publisher: International Press publist_id: '7336' quality_controlled: '1' scopus_import: 1 status: public title: Bogoliubov correction to the mean-field dynamics of interacting bosons type: journal_article user_id: 4435EBFC-F248-11E8-B48F-1D18A9856A87 volume: 21 year: '2017' ...