Dynamical formation of polarons in a Bose-Einstein condensate: A variational approach

authored by: L. A.Pena Ardila
Abstract: We investigate the nonequilibrium dynamics of an impurity coupled to a Bose-Einstein condensate, systematically compared with recent experimental results [M. G. Skou, Nat. Phys. (2021)10.1038/s41567-021-01184-5]. The dynamics of the impurity is tracked down by using a time-dependent variational coherent ansatz. For weak coupling between the impurity and the bath, analytical expressions for the time-dependent contrast are derived, matching quite well with previous findings obtained within a master equation approach. For strong coupling instead, the variational ansatz provides a good quantitative description of the polaron dynamics, in particular, in signaling the transition from the few- to the many-body correlated regime where polarons are expected to form.
Organisation(s): Institute of Theoretical Physics
QuantumFrontiers
Type: Article
Journal: Physical Review A
Volume: 103
ISSN: 2469-9926
Publication date: 23.03.2021
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Atomic and Molecular Physics, and Optics
Electronic version(s): https://arxiv.org/abs/2012.11591 (Access: Open)
https://doi.org/10.1103/PhysRevA.103.033323 (Access: Closed)

BibTeX

@article{a85868f56e6d44be80b414fcde7f7915,
title = "Dynamical formation of polarons in a Bose-Einstein condensate: A variational approach",
abstract = "We investigate the nonequilibrium dynamics of an impurity coupled to a Bose-Einstein condensate, systematically compared with recent experimental results [M. G. Skou, Nat. Phys. (2021)10.1038/s41567-021-01184-5]. The dynamics of the impurity is tracked down by using a time-dependent variational coherent ansatz. For weak coupling between the impurity and the bath, analytical expressions for the time-dependent contrast are derived, matching quite well with previous findings obtained within a master equation approach. For strong coupling instead, the variational ansatz provides a good quantitative description of the polaron dynamics, in particular, in signaling the transition from the few- to the many-body correlated regime where polarons are expected to form.",
author = "Ardila, {L. A.Pena}",
note = "Funding Information: We gratefully acknowledge Kristian K. Nielsen for discussions at an earlier stage of this work. We also thank Magnus G. Skou, Nils Byg J{\o}rgensen, and Jan Artl for insightful discussions and for providing the experimental data. The authors also acknowledge Luis Santos, Fabian Grusdt, Artem Volosniev, and Giacomo Bighin for reading the manuscript and for the critical feedback. Special acknowledgment is given to Roberta Giusteri for critical comments on the manuscript. This research was funded by the DFG Excellence Cluster QuantumFrontiers.",
year = "2021",
month = mar,
day = "23",
doi = "10.1103/PhysRevA.103.033323",
language = "English",
volume = "103",
journal = "Physical Review A",
issn = "2469-9926",
publisher = "American Physical Society",
number = "3",
}