SO(5) superconductor in a Zeeman magnetic field: Phase diagram and thermodynamic properties

TL;DR

This paper models high-temperature superconductors using SO(5) quantum rotor theory under magnetic fields, deriving thermodynamic properties and phase diagrams that align qualitatively with experimental observations.

Contribution

It introduces a spherical approach to analyze the SO(5) quantum rotor model in magnetic fields, providing new formulas for critical lines and thermodynamic quantities.

Findings

Critical lines and thermodynamic properties are derived.

Results qualitatively match experimental data on cuprates.

Temperature dependence of thermodynamic quantities is characterized.

Abstract

In this paper we present calculations of the SO(5) quantum rotor theory of high-T$_{c}$ superconductivity in Zeeman magnetic field. We use the spherical approach for five-component quantum rotors in three-dimensional lattice to obtain formulas for critical lines, free energy, entropy and specific heat and present temperature dependences of these quantities for different values of magnetic field. Our results are in qualitative agreement with relevant experiments on high-T$_{c}$ cuprates.