Crystallographic-dependent bilinear magnetoelectric resistance in a thin WTe$_2$ layer

TL;DR

This study reveals that bilinear magnetoelectric resistance in thin WTe$_2$ layers depends on crystallographic orientation, showing a three-fold symmetry along the a-axis at low temperature, linked to its spin textures.

Contribution

It demonstrates the crystallographic dependence of BMR in WTe$_2$, highlighting the role of crystal symmetry and spin textures in magneto-transport phenomena.

Findings

BMR exhibits a three-fold symmetry along the a-axis at 10 K.

The effect is absent when current is applied along the b-axis.

Both first and second harmonic signals are studied under various conditions.

Abstract

The recently reported Bilinear Magnetoeletric Resistance (BMR) in novel materials with rich spin textures, such as bismuth selenide (Bi$_2$Se$_3$) and tungsten ditelluride (WTe$_2$), opens new possibilities for probing the spin textures via magneto-transport measurements. By its nature, the BMR effect is directly linked to the crystal symmetry of the materials and its spin texture. Therefore, understanding the crystallographic dependency of the effect is crucial. Here we report the observation of crystallographic-dependent BMR in thin WTe$_2$ layers and explore how it is linked to its spin textures. The linear response measured in first harmonic signals and the BMR measured in second harmonic signals are both studied under a wide range of magnitudes and directions of magnetic field, applied current and at different temperatures. We discover a three-fold symmetry contribution of the BMR when current is applied along the a-axis of the WTe$_2$ thin layer at 10 K, which is absent for when current is applied along the b-axis.