Abstract
Compared with their bulk counterparts, two-dimensional (2D) materials can sustain much higher elastic strain (up to ~10%), at which optical quantities such as bandgaps and absorption spectra governing optoelectronic device performance can be modified with relative ease. Using first-principles density functional theory, we show how uniaxial tensile strain can be used to optimize electronic and optical properties of transition metal dichalcogenide lateral (in-plane) heterostructures such as MoX2/WX2 (X = S, Se, Te). In addition we show that a lateral MoS2/MoTe2 heterostructure uniquely develops a continuously varying direct bandgap across the heterojunction, which is a particularly useful characteristic for broad absorption across the solar spectrum. Consequently, we expect these strain-engineered lateral heterostructures to be promising for optimizing optoelectronic device performance by selectively tuning the energetic and spatial distributions of the bandgap.
