Interfacial thermal conductance in 2D WS2/MoSe2 and MoS2/MoSe2 lateral heterostructures

In-plane Transition Metal Dichalcogenides (TMDs) heterostructures hold immense potential for various applications in the modern semiconductor industry, including electronics, optoelectronics, and photovoltaic devices. Different TMD monolayers can be ‘stitched’ together to construct an in-plane (lateral) heterostructure. As different TMD monolayers present different work functions and have their intrinsic shortcomings, a TMD heterostructure is an excellent form to optimize their properties and to achieve the best functionality. This requires a quantitative understanding of the properties of the interfaces in the heterostructures. In this work, we perform nonequilibrium molecular dynamics simulations, based on a parametrized Stillinger-Weber potential, to investigates the thermal conductance of the interfaces in 2D ${\mathrm{WS}}_2/{\mathrm{MoSe}}_2$ and ${\mathrm{MoS}}_2/{\mathrm{MoSe}}_2$ in-plane heterostructures, as well as in 2D lateral ${\mathrm{WS}}_2/{\mathrm{MoSe}}_2$ superlattices. Three distinct types of interfaces, including defect-free coherent interfaces, interfaces with the $5\mid 7$ defects, and the alloy-like incoherent interfaces, are explored. The effects of interphase structure and temperature are quantified. Phonon density of states (PDOS) analysis is used to understand the effect of different interphase structures. The effect of superlattice period on thermal conductance of the superlattices has also been quantified.