Quantum states, linear response in dc, electromagnetic fields for the charge current, spin polarization of electrons at the Bi/Si interface with the giant spin-orbit coupling

摘要

An expansion of the nearly free-electron model constructed by Frantzeskakis, Pons, Grioni [1] describing quantum states at the Bi/Si(111) interface with the giant spin-orbit coupling is developed, applied for the band structure, spin polarization calculation, as well as for the linear response analysis of the charge current, induced spin caused by a dc field, by electromagnetic radiation. It is found that the large spin-orbit coupling in this system may allow resolving the spin-dependent properties even at room temperature, at a realistic collision rate. The geometry of the atomic lattice combined with spin-orbit coupling leads to an anisotropic response for both the current, spin components related to the orientation of the external field. The in-plane dc electric field produces only the in-plane components of spin in the sample, while both the in-plane, out-of-plane spin components can be excited by normally propagating electromagnetic wave with different polarizations.