Two-Dimensional Dresselhaus-Type Spin Texture and Nonreciprocal Magnetoresistance in Magnetic Semiconductor EuIr₄In₂Ge₄

We present the nonreciprocal magnetoresistance (NRMR) and spin texture of the noncentrosymmetric magnetic semiconductor EuIr₄In₂Ge₄. Anisotropy measurements of NRMR for different crystalline axes under rotational magnetic fields revealed a two-dimensional Dresselhaus-type spin texture of this material, where the spin polarization is confined to the tetragonal (001) plane. Strong coupling between NRMR and magnetism was suggested by the low-temperature field dependence of NRMR; however, the magnitude of NRMR was more rapidly suppressed by increasing the temperature than that of magnetic susceptibility. This distinct behavior implies extra mechanisms to reduce the NRMR in addition to the reduction of magnetic moment due to the temperature increase.