Non-Analytic Contributions to the Self-Energy and the Thermodynamics of Two-Dimensional Fermi Liquids

TL;DR

This paper investigates the thermodynamics of two-dimensional Fermi liquids, revealing non-analytic temperature contributions to entropy from self-energy corrections, and finds no fundamental breakdown of Fermi Liquid theory in 2D.

Contribution

It demonstrates that 2D Fermi liquids exhibit T^2 entropy contributions from non-analytic self-energy corrections, aligning their behavior with 3D Fermi liquids.

Findings

T^2 contributions to entropy from interactions

No evidence of Fermi Liquid breakdown in 2D

Self-energy corrections explain thermodynamic behavior

Abstract

We calculate the entropy of a two-dimensional Fermi Liquid(FL) using a model with a contact interaction between fermions. We find that there are $T^2$ contributions to the entropy from interactions separate from those due to the collective modes. These $T^2$ contributions arise from non-analytic corrections to the real part of the self-energy which may be calculated from the leading log dependence of the imaginary part of the self-energy through the Kramers-Kronig relation. We find no evidence of a breakdown in Fermi Liquid theory in 2D and conclude that FL in 2D are similar to 3D FL's.