Coupling function from bath density of states
- Modelling of an open quantum system requires knowledge of parameters that specify how it couples to its environment. However, beyond relaxation rates, realistic parameters for specific environments and materials are rarely known. Here we present a method of inferring the coupling between a generic system and its bosonic (e.g., phononic) environment from the experimentally measurable density of states (DOS). With it we confirm that the DOS of the well-known Debye model for three-dimensional solids is physically equivalent to choosing an Ohmic bath. We further match a real phonon DOS to a series of Lorentzian coupling functions, allowing us to determine coupling parameters for gold, yttrium iron garnet (YIG) and iron as examples. The results illustrate how to obtain material-specific dynamical properties, such as memory kernels. The proposed method opens the door to more accurate modelling of relaxation dynamics, for example for phonon-dominated spin damping in magnetic materials.
Author details: | Somayyeh NematiORCiD, Carsten HenkelORCiDGND, Janet AndersORCiD |
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DOI: | https://doi.org/10.1209/0295-5075/ac7b42 |
ISSN: | 0295-5075 |
ISSN: | 1286-4854 |
Title of parent work (English): | epl : a letters journal exploring the frontiers of physics |
Publisher: | IOP Publ. Ltd. |
Place of publishing: | Bristol |
Publication type: | Article |
Language: | English |
Date of first publication: | 2022/07/28 |
Publication year: | 2022 |
Release date: | 2023/12/08 |
Volume: | 139 |
Issue: | 3 |
Article number: | 36002 |
Number of pages: | 7 |
Funding institution: | University of Potsdam |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
DDC classification: | 5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik |
Peer review: | Referiert |
Publishing method: | Open Access / Hybrid Open-Access |
License (German): | CC-BY - Namensnennung 4.0 International |