Electronics and optoelectronics of lateral heterostructures within monolayer indium monochalcogenides

Abstract

Lateral heterostructures have attracted a great deal of attention due to their advanced properties, which may open up unforeseen opportunities in materials science and device physics. Here, we demonstrate a novel type of lateral heterostructure within monolayer indium monochalcogenides. The thermal stability of the structure is obtained based on the ab initio molecular dynamics calculations. Our results reveal that the proposed lateral heterostructures have direct bandgaps, tunable electronic properties, and type-II band alignment. In addition, the predicted carrier mobilities exceed 10³ cm² (V s)⁻¹, which are 1–2 orders of magnitude higher compared to those of transition metal chalcogenide (TMD) materials. For the first time, the photoresponse and photovoltaic performance of such lateral heterostructures are evaluated based on the first-principles calculations. Upon illumination, the photoinduced current is generated throughout the heterojunction, with an external quantum efficiency up to 7.1%. These results make indium monochalcogenide lateral heterostructures promising candidates for next-generation of electronic and optoelectronic devices.