Polarization characteristics of valley and spin using monolayer MoS2 structure modulated by strain

Abstract

Piezotronics and piezo-phototronics are new emerging fields that have already found applications in nanogenerators, piezoelectric transistors, strain sensors and LEDs. The strain-induced piezoelectric potential plays a crucial role in modulating charge-carrier transport properties in piezoelectric semiconductor materials, especially for two-dimensional (2D) materials. In this work, we theoretically study the piezotronic effect, circularly polarized light and Zeeman field’s impact on the modulation of valley and spin properties in monolayer (ML) MoS2 nanoribbon. We create two ferromagnetic regions in the ML MoS2 nanoribbon to simultaneously manipulate the transport properties of valley and spin using externally applied polarized light and strain. In the proposed junction of ML MoS2, which consists of two barriers modulated by strain, light and Zeeman field, an intriguing coexistence of perfect valley and spin polarization emerges. Our investigation reveals that among these three effects, the huge piezoelectric effect plays a leading role.