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arXiv · 1509.00743

Manipulating Spin-polarized Photocurrent in 2D Transition Metal Dichalcogenides

Xie Lu·Xiaodong Cui
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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 a method of generating spin polarization in monolayer transition metal dichalcogenides (TMD) by the circularly polarized optical pumping. The fully 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 lifetime, the unique valley contrasted physics and the spin-valley locking make monolayer WS2 an unprecedented candidate for semiconductor based spintronics.

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Xie Lu, Xiaodong Cui. 2015-09-02. Manipulating Spin-polarized Photocurrent in 2D Transition Metal Dichalcogenides. https://doi.org/10.1073/pnas.1523012113

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