Hall helps Ohm: some corrections to negative-U centers approach to transport properties of YBa$_2$Cu$_3$O$_x$ and La$_{2-x}$Sr$_x$CuO$_4$

TL;DR

This paper models the temperature dependence of resistivity and Hall coefficient in cuprate superconductors YBCO and LSCO using a negative-U centers approach, accounting for anisotropy and carrier dynamics.

Contribution

It introduces a comprehensive model incorporating negative-U centers and anisotropy effects to explain transport properties in cuprates across doping levels.

Findings

Calculated resistivity matches experimental data across doping ranges.

Anisotropy affects magnitude but not temperature dependence of transport properties.

Negative-U centers effectively model chemical potential and effective mass variations.

Abstract

For broad oxygen and strontium doping ranges, temperature dependences (T-dependences) of the normal state resistivity \rho(T) of YBa_2Cu_3O_x (YBCO) and La_(2-x)Sr_xCuO_4 (LSCO) are calculated and compared to experiments. Holes transport was taken in the \tau-approximation, where \tau(T,\epsilon) is due to acoustic phonons. Besides, T-dependence of the chemical potential \mu(T) and effective carrier mass m* ~10-100 free electron masses, obtained by negative-U centers modelling the T-dependence of the Hall coefficient, were used to calculate \rho(T). In addition, it is demonstrated that anisotropy of the cuprates does not affect the calculated T-variation of neither Hall coefficient nor \rho, but only rescale their magnitudes by factors depending on combinations of m_ab and m_c.