Extended Kohler's Rule of Magnetoresistance in TaCo${}_2$Te${}_2$

TaCo${}_2$Te${}_2$ is recently reported to be an air-stable, high mobility Van der Waals material with probable magnetic order. Here we investigate the scaling behavior of its magnetoresistance. We measured both the longitudinal (${\rho }_{xx}$) and Hall (${\rho }_{xy}$) magnetoresistivities of TaCo${}_2$Te${}_2$ crystals in magnetic fields parallel to the c-axis and found that the magnetoresistance violates the Kohler’s rule $MR\sim f[H\mathrm{/}{\rho }_0]$ while obeying the extended Kohler’s rule $MR\sim f[H\mathrm{/}(n_T{\rho }_0)]$, where $MR\sim [{\rho }_{xx}(H)-{\rho }_0]\mathrm{/}{\rho }_0$, $H$ is the magnetic field, $n_T$ is a thermal factor, ${\rho }_{xx}(H)$ and ${\rho }_0$ are the resistivities at $H$ and zero field, respectively. While deviating from those of the densities of electrons ($n_e$) and holes ($n_h$) obtained from the two-band model analysis of the magnetoconductivities, the temperature dependence of $n_T$ is close to that of the Hall carrier densities $n_H$ calculated from the slopes of ${\rho }_{xy}(H)$ curves at low magnetic fields, providing a new way to obtain the thermal factor in the extended Kohler’s rule.