Collective excitations and stability of a non-Fermi liquid state near a quantum-critical point of a metal

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gindikin, Yasha, Maslov, Dmitrii L., Chubukov, Andrey V.
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912669438574592
author Gindikin, Yasha
Maslov, Dmitrii L.
Chubukov, Andrey V.
author_facet Gindikin, Yasha
Maslov, Dmitrii L.
Chubukov, Andrey V.
contents We examine the spectral properties of collective excitations with finite angular momentum $l$ for a system of interacting fermions near a Pomeranchuk quantum critical point, both in the Fermi liquid and non-Fermi liquid regimes. Previous studies found that deep in the Fermi liquid regime, the spectral functions for even and odd $l$ behave differently - the latter is suppressed compared to the former because of kinematic constraints on scattering processes. The main focus of our paper is to understand how the spectral functions for even and odd $l$ evolve as the system enters the non-Fermi liquid regime. We obtain the full scaling function for the electron polarization bubble at arbitrary $l$, which interpolates between the Fermi liquid and non-Fermi liquid regimes. We show that collective excitations for all $l$ remain stable and causal throughout the crossover and right at the quantum critical point.
format Preprint
id arxiv_https___arxiv_org_abs_2505_08925
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Collective excitations and stability of a non-Fermi liquid state near a quantum-critical point of a metal
Gindikin, Yasha
Maslov, Dmitrii L.
Chubukov, Andrey V.
Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
We examine the spectral properties of collective excitations with finite angular momentum $l$ for a system of interacting fermions near a Pomeranchuk quantum critical point, both in the Fermi liquid and non-Fermi liquid regimes. Previous studies found that deep in the Fermi liquid regime, the spectral functions for even and odd $l$ behave differently - the latter is suppressed compared to the former because of kinematic constraints on scattering processes. The main focus of our paper is to understand how the spectral functions for even and odd $l$ evolve as the system enters the non-Fermi liquid regime. We obtain the full scaling function for the electron polarization bubble at arbitrary $l$, which interpolates between the Fermi liquid and non-Fermi liquid regimes. We show that collective excitations for all $l$ remain stable and causal throughout the crossover and right at the quantum critical point.
title Collective excitations and stability of a non-Fermi liquid state near a quantum-critical point of a metal
topic Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2505.08925