Dynamical Variational Approach to Bose Polarons at Finite Temperatures
Dzsotjan D, Schmidt R, Fleischhauer M (2020)
Publication Type: Journal article
Publication year: 2020
Journal
Book Volume: 124
Article Number: 223401
Journal Issue: 22
DOI: 10.1103/PhysRevLett.124.223401
Abstract
We discuss the interaction of a mobile quantum impurity with a Bose-Einstein condensate of atoms at finite temperature. To describe the resulting Bose polaron formation we develop a dynamical variational approach applicable to an initial thermal gas of Bogoliubov phonons. We study the polaron formation after switching on the interaction, e.g., by a radio-frequency (rf) pulse from a noninteracting to an interacting state. To treat also the strongly interacting regime, interaction terms beyond the Fröhlich model are taken into account. We calculate the real-time impurity Green's function and discuss its temperature dependence. Furthermore we determine the rf absorption spectrum and find good agreement with recent experimental observations. We predict temperature-induced shifts and a substantial broadening of spectral lines. The analysis of the real-time Green's function reveals a crossover to a linear temperature dependence of the thermal decay rate of Bose polarons as unitary interactions are approached.
Involved external institutions
Technische Universität Kaiserslautern
Germany (DE)
Max-Planck-Institute of Quantum Optics (MPQ) / Max-Planck-Institut für Quantenoptik
Germany (DE)
Germany (DE)
Max-Planck-Institute of Quantum Optics (MPQ) / Max-Planck-Institut für Quantenoptik
Germany (DE)
How to cite
APA:
Dzsotjan, D., Schmidt, R., & Fleischhauer, M. (2020). Dynamical Variational Approach to Bose Polarons at Finite Temperatures. Physical Review Letters, 124(22). https://dx.doi.org/10.1103/PhysRevLett.124.223401
MLA:
Dzsotjan, David, Richard Schmidt, and Michael Fleischhauer. "Dynamical Variational Approach to Bose Polarons at Finite Temperatures." Physical Review Letters 124.22 (2020).
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