Many Fermi polarons at nonzero temperature

Hiroyuki Tajima, Shun Uchino

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

An extremely polarized mixture of an ultracold Fermi gas is expected to reduce to a Fermi polaron system, which consists of a single impurity immersed in the Fermi sea of majority atoms. By developing a many-body T-matrix theory, we investigate spectral properties of the polarized mixture in experimentally relevant regimes in which the system of finite impurity concentration at nonzero temperature is concerned. We explicitly demonstrate presence of polaron physics in the polarized limit and discuss effects of many polarons in an intermediate regime in a selfconsistent manner. By analyzing the spectral function at finite impurity concentration, we extract the attractive and repulsive polaron energies. We find that a renormalization of majority atoms via an interaction with minority atoms and a thermal depletion of the impurity chemical potential are of significance to depict the many-polaron regime.

Original languageEnglish
Article number073048
JournalNew Journal of Physics
Volume20
Issue number7
DOIs
Publication statusPublished - 2018 Jul 1

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polarons
impurities
atoms
temperature
matrix theory
minorities
depletion
physics
gases
interactions
energy

Keywords

  • Fermi polaron
  • pairing fluctuations
  • ultracold Fermi gas

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Many Fermi polarons at nonzero temperature. / Tajima, Hiroyuki; Uchino, Shun.

In: New Journal of Physics, Vol. 20, No. 7, 073048, 01.07.2018.

Research output: Contribution to journalArticle

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