Hall-Lorenz ratio of YBa2Cu3O7 using Ionization energy based Fermi-Dirac statistics and charge-spin separation

TL;DR

This paper models the temperature-dependent electronic and thermal properties of YBa2Cu3O7 using ionization energy based Fermi-Dirac statistics and charge-spin separation, aligning well with experimental data.

Contribution

It introduces a novel approach combining ionization energy based Fermi-Dirac statistics with charge-spin separation to analyze high-temperature superconductor properties.

Findings

Hall-Lorenz ratio varies linearly with temperature, matching experiments.

Heat conductivity increases as temperature decreases above Tc.

Heat capacity behavior aligns qualitatively with experimental observations.

Abstract

The temperature dependent properties of heat capacity, heat conductivity and Hall-Lorenz ratio have been solved numerically after taking the previously proposed ionization energy based Fermi-Dirac statistics and the coexistence of Fermi and charge-spin separated liquid into account. The thermo-magneto-electronic properties are entirely for spin and charge carriers, hence the phonon contribution has been neglected. A linear dependence between the Hall-Lorenz ratio and temperature ($T$) is also obtained in accordance with the experimental results for overdoped YBa$_2$Cu$_3$O$_{7-\delta}$, if these conditions, $E_I$ $<$ $T_c$ with respect to resistivity and there are no spinon pairings ($T^*$ = 0) are satisfied. Heat conductivity based on both pure and electron-contaminated charge-spin separated liquid in $ab$-planes above $T_c$ are found to increase with decreasing $T$ as a consequence of inverse proportionality with $T$. The $T$-dependence of heat capacity are also highlighted, which qualitatively complies with the experimental findings.