Energy band realignment at the interfaces between materials in heterostructures can give rise to unique electronic characteristics and non-trivial low-dimensional charge states. In a homojunction of monolayer and multilayer MoS2, the thickness-dependent band structure implies the possibility of band realignment and a new interface charge state with properties distinct from the isolated layers. In this report, we probe the interface charge state using scanning photocurrent microscopy and gate-dependent transport with source-drain bias applied along the interface. Enhanced photoresponse observed at the interface is attributed to band bending. The effective conductivity of a material with a monolayer-multilayer interface of MoS2 is demonstrated to be higher than that of independent monolayers or multilayers of MoS2. A classic heterostructure model is constructed to interpret the electrical properties at the interface. Our work reveals that the band engineering at the transition metal dichalcogenides monolayer/multilayer interfaces can enhance the longitudinal conductance and field-effect mobility of the composite monolayer and multilayer devices.
@article{arxiv.1612.03921,
title = {Enhanced Conductivity Along Lateral Homojunction Interfaces of Atomically Thin Semiconductors},
author = {Ying Jia and Teodor K. Stanev and Erik J. Lenferink and Nathaniel P. Stern},
journal= {arXiv preprint arXiv:1612.03921},
year = {2017}
}