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arXiv · 1903.12592

Boundary conditions for spin and charge diffusion in the presence of interfacial spin-orbit coupling

Juan Borge·Ilya V. Tokatly
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Abstract

Breaking of the inversion symmetry at the interface between different materials may dramatically enhance spin-orbit interaction in the vicinity of the interface. We incorporate the effects of this interfacial spin-orbit coupling (ISOC) into the standard drift-diffusion theory by deriving generalized boundary conditions for diffusion equations. Our theoretical scheme is based on symmetry arguments, providing a natural classification and parametrization of all spin-charge and spin-spin conversion effects that occur due to ISOC at macroscopically isotropic interfaces between nonmagnetic materials. We illustrate our approach with specific examples of spin-charge conversion in hybrid structures. In particular, for a lateral metal-insulator structure we predict an "ISOC-gating" effect which can be used to detect spin currents in metallic films with weak bulk SOC.

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Juan Borge, Ilya V. Tokatly. 2019-03-29. Boundary conditions for spin and charge diffusion in the presence of interfacial spin-orbit coupling. https://doi.org/10.1103/physrevb.99.241401

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