Superconductivity and superconducting order parameter phase fluctuations in a weakly doped antiferromagnet

TL;DR

This paper investigates the effects of phase fluctuations on superconductivity in a weakly doped antiferromagnet model, with implications for understanding high-temperature superconductors.

Contribution

It introduces a phenomenological model considering phase fluctuations and doped charge carrier localization, analyzing its superconducting properties and doping dependence.

Findings

Superconducting gap varies with doping and temperature.

Phase fluctuations significantly influence superconductivity.

Model aligns with ARPES observations in cuprates.

Abstract

The superconducting properties of a recently proposed phenomenological model for a weakly doped antiferromagnet are analyzed, taking into account fluctuations of the phase of the order parameter. In this model, we assume that the doped charge carriers can't move out of the antiferromagnetic sublattice they were introduced. This case corresponds to the free carrier spectra with the maximum at ${\bf k}=(\pm \pi /2 ,\pm \pi /2)$, as it was observed in ARPES experiments in some of the cuprates in the insulating state [1]. The doping dependence of the superconducting gap and the temperature-carrier density phase diagram of the model are studied in the case of the $d_{x^{2}-y^{2}}$ pairing symmetry and different values of the effective coupling. A possible relevance of the results to the experiments on high-temperature superconductors is discussed.