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

P. Walmsley: I. R. Fisher; REVIEW OF SCIENTIFIC INSTRUMENTS, 04/05/17.

Additional Authors: I. R. Fisher

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 π/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 ErTe3, and it is concluded that this method presents a significant improvement on existing techniques, particularly when measuring small anisotropies.