Effects of thermal phase fluctuations in a 2D superconductor: an exact result for the spectral function

TL;DR

This paper derives an exact expression for the spectral function of a 2D superconductor experiencing strong thermal phase fluctuations, providing insights into its single-particle properties in a specific regime.

Contribution

It presents an exact analytical result for the spectral function of a 2D superconductor under thermal phase fluctuations, a novel achievement in the field.

Findings

Exact spectral function expression derived

Applicable in the regime of small superconducting gap compared to Fermi energy

Enhances understanding of thermal fluctuation effects in 2D superconductors

Abstract

We consider the single particle spectral function for a two-dimensional clean superconductor in a regime of strong critical thermal phase fluctuations. In the limit where the maximum of the superconducting gap is much smaller than the Fermi energy we obtain an exact expression for the spectral function integrated over the momentum component perpendicular to the Fermi surface.