Strain forces tuned the electronic and optical properties in GaTe/MoS van der Waals heterostructures.

Two-dimensional (2D) van der Waals heterostructures (vdWHs) have attracted widespread attention in fundamental materials science and device physics. In this work, we report a novel GaTe/MoS vdWH and theoretically investigate the electronic and optical properties based on first-principles calculations. GaTe/MoS vdWH possesses an indirect band gap with type-II band alignment. Meanwhile, the interfacial charge transfer from MoS to GaTe can effectively separate electrons and holes. Also, this vdWH shows improved visible-ultraviolet optical absorption properties compared with those of the isolated GaTe or MoS monolayers. More remarkably, the biaxial strain can not only modulate the band gap but also enhance the optical performance in GaTe/MoS vdWH. In particular, the tensile strain is more effective for improving the optical absorption in the visible light region. These findings indicate that GaTe/MoS vdWH is a promising candidate for nanoelectronics and optoelectronic devices.