Spectrum of density, spin and pairing fluctuations of an attractive two-dimensional Fermi gas

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Apostoli, Christian, Kelly, Patrick, Lopez, Annette, Dauer, Kaelyn, Bertaina, Gianluca, Galli, Davide Emilio, Vitali, Ettore
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912015000272896
author Apostoli, Christian
Kelly, Patrick
Lopez, Annette
Dauer, Kaelyn
Bertaina, Gianluca
Galli, Davide Emilio
Vitali, Ettore
author_facet Apostoli, Christian
Kelly, Patrick
Lopez, Annette
Dauer, Kaelyn
Bertaina, Gianluca
Galli, Davide Emilio
Vitali, Ettore
contents We leverage random phase approximation and unbiased auxiliary-field quantum Monte Carlo methods to compute dynamical correlations for a dilute homogeneous two-dimensional attractive Fermi gas. Our main purpose is to quantitatively study the collective excitations of the system to generate robust benchmark results and to shed light into fermionic superfluidity in the strongly correlated regime. In particular we are motivated by a recent paper suggesting that the Higgs mode can be detected in the spectrum of spin fluctuations. Despite the fact that we are somewhat limited by finite-size effects, our study pinpoints indeed a clear peak in the spin channel at low momentum, but a detailed analysis suggests that such a peak, though certainly interesting, does not correspond to the Higgs mode. We propose a different explanation for the shape of the spin structure factor. On the other hand, our results clearly show that the Higgs mode can be detected in the density channel at very small wave vectors, although very good resolution is necessary.
format Preprint
id arxiv_https___arxiv_org_abs_2403_13636
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Spectrum of density, spin and pairing fluctuations of an attractive two-dimensional Fermi gas
Apostoli, Christian
Kelly, Patrick
Lopez, Annette
Dauer, Kaelyn
Bertaina, Gianluca
Galli, Davide Emilio
Vitali, Ettore
Quantum Gases
We leverage random phase approximation and unbiased auxiliary-field quantum Monte Carlo methods to compute dynamical correlations for a dilute homogeneous two-dimensional attractive Fermi gas. Our main purpose is to quantitatively study the collective excitations of the system to generate robust benchmark results and to shed light into fermionic superfluidity in the strongly correlated regime. In particular we are motivated by a recent paper suggesting that the Higgs mode can be detected in the spectrum of spin fluctuations. Despite the fact that we are somewhat limited by finite-size effects, our study pinpoints indeed a clear peak in the spin channel at low momentum, but a detailed analysis suggests that such a peak, though certainly interesting, does not correspond to the Higgs mode. We propose a different explanation for the shape of the spin structure factor. On the other hand, our results clearly show that the Higgs mode can be detected in the density channel at very small wave vectors, although very good resolution is necessary.
title Spectrum of density, spin and pairing fluctuations of an attractive two-dimensional Fermi gas
topic Quantum Gases
url https://arxiv.org/abs/2403.13636