Hall effect on the triangular lattice

TL;DR

This paper analyzes the high-frequency Hall effect on a 2D triangular lattice with interactions, revealing temperature-dependent behaviors and comparing results with experimental data in cobaltates.

Contribution

It provides a comprehensive analytical and numerical study of the Hall coefficient's temperature and doping dependence on a triangular lattice with interactions.

Findings

$R_H$ follows the semiclassical $1/qn^*$ law at T=0

$R_H$ shows a linear T dependence at high temperature

Results are compared with experimental Hall measurements in cobaltates

Abstract

We investigate the high frequency Hall effect on a two-dimensional triangular lattice with nearest-neighbor hopping and a local Hubbard interaction. The complete temperature and doping dependencies of the high-frequency Hall coefficient $R_H$ are evaluated analytically and numerically for small, intermediate, and strong interactions using various approximation schemes. We find that $R_H$ follows the semiclassical $1/qn^*$ law near T=0, but exhibits a striking $T$-linear behavior with an interaction- and doping-dependent slope at high temperature. We compare our results with previous theories as well as Hall measurements performed in the cobaltates.