Piezotronic spin and valley transistors based on monolayer MoS2

Piezotronics and piezo-phototronics based on the third generation semiconductors are two novel fields for low power consumption, self-powered technology and internet of things. Strain-induced piezoelectric field plays a key role to modulate not only charge-carrier transport but also quantum transport properties in piezoelectric semiconductors, especially for two-dimensional materials which can withstand large strain. In this paper, we theoretically study piezotronic effect on the modulation of spin and valley properties in single-layered MoS2. Spin- and valley-dependent conductance, electronic density distribution and polarization ratio are investigated by quantum transport calculation. Because of piezotronic effect, strain-gated spin and valley transistors have excellent quantum state selectivity using by strain. Our work provides not only piezotronic effect on spin and valley quantum states, but also a guidance for designing novel quantum piezotronic devices.