d-Wave Order Parameter in Bi2212 from a Phenomenological Model of High T$_c$ Cuprates

TL;DR

This paper uses a phenomenological lattice model with phase fluctuations within the BCS framework to interpret ARPES data on Bi2212, estimating the KT transition temperature and phase boundaries, aligning qualitatively with experimental doping trends.

Contribution

It introduces a model incorporating phase fluctuations to analyze the d-wave order parameter and transition temperatures in high-Tc cuprates, fitting ARPES data.

Findings

Estimated KT transition temperature below mean field T_c.

Determined phase boundaries between different order parameter symmetries.

Model parameters fit ARPES gap data for d_{x^2-y^2} symmetry.

Abstract

A phenomenological lattice model of high $T_c$ cuprates including order parameter phase fluctuations is considered within the BCS approximation, to interpret the experimental data from ARPES measurements on Bi2212 samples. A Kosterlitz-Thouless (KT) transition temperature $T_c^{KT}$ is estimated below the mean field transition $T_c^{MF}$, phase boundaries between competing order parameters of different symmetries are obtained and best model parameters, fitting the ARPES gap of $d_{x^2-y^2}$ symmetry, are determined. Variation of $T_c^{KT}$, as a function of the dopant concentration $\delta$, is in qualitative agreement with experiments.