Non-reciprocal Magnetoresistances in Chiral Tellurium

TL;DR

This paper investigates non-reciprocal magnetoresistance effects in chiral Tellurium, revealing multiple mechanisms such as the Edelstein and Nernst effects that depend on the magnetic field direction and material chirality.

Contribution

It provides a systematic analysis of angular-dependent magnetoresistance in chiral Tellurium, identifying distinct mechanisms responsible for non-reciprocal effects along different axes.

Findings

Edelstein effect causes non-reciprocity along the z-axis.

Nernst effect explains signals along the y-axis.

Orbital magnetizations may cause effects along the x-axis.

Abstract

Materials with broken fundamental symmetries, such as chiral crystals, provide a rich playground for exploring unconventional spin-dependent transport phenomena. The interplay between a material's chirality, strong spin-orbit coupling, and charge currents can lead to complex non-reciprocal effects, where electrical resistance depends on the direction of current and magnetic fields. In this study, we systematically investigate the angular dependencies of magnetoresistance in single-crystalline chiral Tellurium (Te). We observe distinct non-reciprocal magnetoresistances for magnetic fields applied along three orthogonal directions: parallel to the current along the chiral axis (z), in the sample plane but perpendicular to the current (y), and out of the sample plane (x). Through detailed analysis of the chirality- and thickness-dependence of the signals, we successfully disentangle multiple coexisting mechanisms. We conclude that the Edelstein effect, arising from the chiral structure's radial spin texture, is responsible for the non-reciprocity along the z-axis. In contrast, the chirality-independent signal along the y-axis is attributed to the Nernst effect, and the non-reciprocity along the x-axis may originate from intrinsic orbital magnetizations. These findings elucidate the complex interplay of spin, orbital, and thermal effects in Te, providing a complete picture of its non-reciprocal transport properties.