Generation and Detection of Dresselhaus-Like Spin Current in a Single-Crystal Ferromagnetic Metal

Distinct from the existing spin-orbit torque devices to only generate Rashba-like spin current, it is proposed to generate Dresselhaus-like spin current based on a single-crystal ferromagnetic metal. By employing the second harmonic Hall measurement, it is found that the second harmonic Hall signal in single-crystal ferromagnet exhibits an antisymmetric angular dependence induced by Dresselhaus-like spin current, opposite to the reported symmetric angular dependence induced by Rashba-like spin current. Such anomalous Dresselhaus-like spin current is further confirmed by the current-induced shift of the hysteresis loop when the magnetic field is swept along the current direction. However, when the ferromagnetic metal exhibits amorphous crystal structure or polycrystal structure, the Dresselhaus-like spin current is absent. This result complements the missing type of spin currents due to charge-to-spin conversion and benefits the formulation of comprehensive spin-orbit coupling mechanism, by considering additional broken symmetry caused by ferromagnetic order and the structure symmetry of the crystalline lattice.