Photon-induced spin transport in two-dimensional electron systems

• Main Author: Korostil, A.
• Format: Article
• Language: English
• Published: Інститут проблем моделювання в енергетиці ім. Г.Є. Пухова НАН України 2011
• Series: Збірник наукових праць Інституту проблем моделювання в енергетиці ім. Г.Є. Пухова НАН України
• Online Access: http://dspace.nbuv.gov.ua/handle/123456789/28550

We study spin-dependent transport in a two-dimensional electron gas subject to an external step-like potential V(x) and irradiated by an electromagnetic field (EF). In the absence of EF the electronic spectrum splits into spin sub-bands originating from the "Rashba" spin-orbit coupling. We show that the resonant interaction of propagating electrons with the component EF parallel to the barrier induces a nonequilibrium dynamic gap (2ΔR ) between the spin sub-bands. Existence of this gap results in coherent spin-flip processes that lead to a spin-polarized current and a large magnetoresistance, i.e. the spin valve effect. These effects may be used for controlling spin transport in semiconducting nanostructures, e.g. spin transistors, spin-blockade devices etc., by variation of the intensity S and frequency ω of the external radiation.