Yang, LP (reprint author), Inst Theoret Phys, State Key Lab Theoret Phys, Beijing 100190, Peoples R China.
Spin-orbit coupling (SOC) can mediate the electric-dipole spin resonance (EDSR) within an a.c. electric field. By applying a quantum linear coordinate transformation, we find that the essence of EDSR could be understood as a spin precession under an effective a.c. magnetic field induced by the SOC in the reference frame, which is following exactly the classical trajectory of this spin. Based on this observation, we find an upper limit for the spin-flipping speed in the EDSR-based control of spin. For two-dimensional case, the azimuthal dependence of the effective magnetic field can be used to measure the ratio of the Rashba and Dresselhaus SOC strengths.