Spin-accumulation and spin-transport effects induced by surface plasmon-polariton waves

Abstract

A surface plasmon-polariton (SPP) wave forms highly inhomogeneous intensity distribution near the metal-dielectric interface, and this light field produces the inhomogeneous magnetization of the metal. Recently [Phys. Rev. B 101, 161404 (2020)PRBMDO0163-182910.1103/PhysRevB.101.161404; Phys. Rev. B 102, 125431 (2020)PRBMDO0163-182910.1103/PhysRevB.102.125431], the SPP-induced magnetization was considered theoretically as a source of purposeful excitation and control of the spin-transport phenomena. Here, this problem is revisited with the refined boundary conditions for the spin-diffusion equation. The improved theoretical description of the light-induced spin accumulation and spin current is formulated. The validity limits of the stationary spin-accumulation model are discussed and numerically estimated. Numerical simulations based on the Drude model for electron gas in metal confirm the general weakness of the SPP-induced spin-transport phenomena but also indicate possibilities of their enhancement and detectable manifestations via employment of high-power short-pulse excitation. The results can be useful for the studies and applications of the SPP-induced effects, in particular, for the development of optically driven spintronic devices.