Current direction dependent magnetotransport in CuTe

Despite being a layered, easily-exfoliated compound, copper monotelluride (CuTe) features an unusual quasi-one-dimensional charge density wave below $T_{\mathrm{C}\mathrm{D}\mathrm{W}}\approx 335$ K. Within a CuTe layer, the electrical resistivity depends sensitively on the direction of the electrical current. Here, we use magnetotransport to probe the metallic state of CuTe with two distinct in-plane current directions. When the current flows along the $a$-axis ($I\mathrm{/}\mathrm{/}a$), the magnetoresistance exhibits a downward curvature as the magnetic field increases. On the other hand, when the current is along the $b$-axis ($I\mathrm{/}\mathrm{/}b$), the magnetoresistance shows the opposite curvature. Our analysis uncovers a violation of Kohler scaling, but only for $I\mathrm{/}\mathrm{/}a$. Shubnikov-de Haas oscillations are detected at low temperatures. Our results shed light on the nature of the metallic state in CuTe with the development of the charge density wave.