Classical Phase Fluctuations in High Temperature Superconductors

TL;DR

This paper investigates classical phase fluctuations in high-temperature superconductors using an XY model, revealing that superfluid density at zero temperature predicts critical temperature and exhibits T-linear behavior at low temperatures, consistent with experiments.

Contribution

It provides a detailed analysis of phase fluctuations in cuprates with a low-temperature expansion and Monte Carlo simulations, highlighting the robustness of superfluid density as a predictor of Tc.

Findings

Superfluid density at T=0 predicts Tc accurately.

Superfluid density decreases with temperature, showing T-linear behavior at low T.

Results align with experimental observations of cuprates.

Abstract

Phase fluctuations of the superconducting order parameter play a larger role in the cuprates than in conventional BCS superconductors because of the low superfluid density of a doped insulator. In this paper, we analyze an XY model of classical phase fluctuations in the high temperature superconductors using a low-temperature expansion and Monte Carlo simulations. In agreement with experiment, the value of the superfluid density at temperature T=0 is a quite robust predictor of Tc, and the evolution of the superfluid density with T, including its T-linear behavior at low temperature, is insensitive to microscopic details.