title: Manipulating spin-polarized photocurrents in 2D transition metal dichalcogenides.
abstract: Manipulating spin polarization of electrons in nonmagnetic semiconductors by means of electric fields or optical fields is an essential theme of the conceptual nonmagnetic semiconductor-based spintronics. Here we experimentally demonstrate an electric method of detecting spin polarization in monolayer transition metal dichalcogenides (TMDs) generated by circularly polarized optical pumping. The spin-polarized photocurrent is achieved through the valley-dependent optical selection rules and the spin-valley locking in monolayer WS2, and electrically detected by a lateral spin-valve structure with ferromagnetic contacts. The demonstrated long spin-valley lifetime, the unique valley-contrasted physics, and the spin-valley locking make monolayer WS2 an unprecedented candidate for semiconductor-based spintronics.
authors.affiliation: Physics Department, University of Hong Kong, Hong Kong.
authors.forename: Lu
authors.initials: L
authors.lastname: Xie
authors.affiliation: Physics Department, University of Hong Kong, Hong Kong xdcui@hku.hk.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Cui
keywords: monolayer transition metal dichalcogenides; spin lifetime; spintronics; spin–valley coupling; valley lifetime