Image of the week: strain and molybdenum disulphide

By Jennifer Sanders on August 24, 2015

For some time, graphene has been touted as a wonder material. Unfortunately, having no bandgap means it isn’t the best candidate material for electronic applications. Comparatively, molybdenum disulphide, (MoS₂) — part of the family of transition metal dichalcogenides — has a non-zero bandgap, making it a 2D material with potential application in future electronic devices.

In a recent paper published in JPhysD, collaborators from Iran, Austria and Italy have investigated the effect of strain on the mobility of single-layer MoS₂. By employing both ab initio simulations and the linearized Boltzman transport equation (BTE), Manouchehr Hosseini et al, concluded that mobility is proportional to tensile strain along the armchair direction, and under compressive strain the mobility becomes non-monotonic as the magnitude of the strain varies.

The below figure shows equi-energy contours for single-layer MoS₂ under a variety of strain conditions along the different directions, as well as an effective mass plot which is nearly circular in shape, confirming the assumption of isotropic bandstructure.