Photoinduced inverse spin-Hall effect: Conversion of light-polarization information into electric voltage

The photoinduced inverse spin-Hall effect was observed in a Pt/GaAs hybrid structure. In the GaAs layer, circularly polarized light generates spin-polarized carriers, inducing a pure spin current into the Pt layer through the interface. This pure spin current is, by the inverse spin-Hall effect in the Pt layer, converted into electric voltage. By changing the direction and ellipticity of the circularly polarized light, the electromotive force varies systematically, consistent with the prediction of the photoinduced inverse spin-Hall effect. The observed phenomenon allows the direct conversion of circular-polarization information into electric voltage; this phenomenon can be used as a spin photodetector.