Surface anisotropic magnetoresistance in the antiferromagnetic semiconductor CrSb2

We report on large anisotropic magnetoresistance (AMR) in surface states of an antiferromagnetic semiconductor $\mathrm{Cr}{\mathrm{Sb}}₂$. The low-temperature measurement of angle-dependent magnetoresistance (ADMR) is performed in high magnetic fields up to 24 T. At 1.4 K, where the surface conduction is dominant, ADMR exhibits clear twofold symmetry consistent with AMR due to magnetic-field-induced change of antiparallel magnetic structure. The AMR magnitude reaches 9.3% despite the small angle dependence of the net magnetic moments, suggesting strong spin-orbit interaction in the surface conduction layer.