Enhanced linear magnetoresistance of germanium at room temperature due to surface imperfection

We report an enhanced linear magnetoresistance in germanium at room temperature. The magnetic-field dependence shows no saturation at magnetic fields (B) up to 4 T and the magnetoresistance sensitivity at low fields (B < 0.4 T) can reach ∼8 T−1. It is found that this magnetoresistance effect is ascribed to surface imperfection, which cannot only increase the recombination rate but also enhance the inhomogeneity. Our work may be attractive to the magnetic-field sensing industry and make germanium-based magnetoelectronics further developed.