Theory of the spectral function of Fermi polarons at finite temperature

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Hu, Hui, Wang, Jia, Liu, Xia-Ji
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866916362324017152
author Hu, Hui
Wang, Jia
Liu, Xia-Ji
author_facet Hu, Hui
Wang, Jia
Liu, Xia-Ji
contents We develop a general theory of Fermi polarons at nonzero temperature, including particle-hole excitations of the Fermi sea shake-up to arbitrarily high orders. The exact set of equations of the spectral function is derived by using both Chevy ansatz and diagrammatic approach, and their equivalence is clarified to hold in free space only, with an unregularized infinitesimal interaction strength. The correction to the polaron spectral function arising from two-particle-hole excitations is explicitly examined, for an exemplary case of Fermi polarons in one-dimensional optical lattices. We find quantitative improvements at low temperatures with the inclusion of two-particle-hole excitations, in both polaron energies and decay rates. Our exact theory of Fermi polarons with arbitrary orders of particle-hole excitations might be used to better understand the intriguing polaron dynamical responses in two or three dimensions, whether in free space or within lattices.
format Preprint
id arxiv_https___arxiv_org_abs_2402_11805
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Theory of the spectral function of Fermi polarons at finite temperature
Hu, Hui
Wang, Jia
Liu, Xia-Ji
Quantum Gases
Strongly Correlated Electrons
We develop a general theory of Fermi polarons at nonzero temperature, including particle-hole excitations of the Fermi sea shake-up to arbitrarily high orders. The exact set of equations of the spectral function is derived by using both Chevy ansatz and diagrammatic approach, and their equivalence is clarified to hold in free space only, with an unregularized infinitesimal interaction strength. The correction to the polaron spectral function arising from two-particle-hole excitations is explicitly examined, for an exemplary case of Fermi polarons in one-dimensional optical lattices. We find quantitative improvements at low temperatures with the inclusion of two-particle-hole excitations, in both polaron energies and decay rates. Our exact theory of Fermi polarons with arbitrary orders of particle-hole excitations might be used to better understand the intriguing polaron dynamical responses in two or three dimensions, whether in free space or within lattices.
title Theory of the spectral function of Fermi polarons at finite temperature
topic Quantum Gases
Strongly Correlated Electrons
url https://arxiv.org/abs/2402.11805