Determination of the resistivity anisotropy of orthorhombic materials via transverse resistivity measurements

TL;DR

This paper introduces a novel, single-measurement method using transverse resistivity to accurately determine resistivity anisotropy in orthorhombic materials, reducing systematic errors and improving upon existing techniques.

Contribution

A new approach utilizing a $rac{ ext{pi}}{4}$ rotation of measurement frame enables direct anisotropy measurement from a single crystal, simplifying and enhancing accuracy.

Findings

Method successfully applied to ErTe$_3$.

Significant reduction in systematic errors.

Improved accuracy over conventional techniques.

Abstract

Measurements of the resistivity anisotropy can provide crucial information about the electronic structure and scattering processes in anisotropic and low-dimensional materials, but quantitative measurements by conventional means often suffer very significant systematic errors. Here we describe a novel approach to measuring the resistivity anisotropy of orthorhombic materials, using a single crystal and a single measurement, that is derived from a $\frac{\pi}{4}$ rotation of the measurement frame relative to the crystallographic axes. In this new basis the transverse resistivity gives a direct measurement of the resistivity anisotropy, which combined with the longitudinal resistivity also gives the in-plane elements of the conventional resistivity tensor via a 5-point contact geometry. This is demonstrated through application to the charge-density wave compound ErTe$_3$, and it is concluded that this method presents a significant improvement on existing techniques in many scenarios.