Second-Order Nonlinear Optical Properties of Monolayer Transition-Metal Dichalcogenides by Computational Analysis

The second-order nonlinear optical properties of monolayer transition-metal dichalcogenides (TMDs) have been drawing increasing interest; yet, challenges remain in the measurements of the response. In this work, we report a first-principles analysis of the second-order nonlinear optical response of monolayer TMDs for transition metals from group V and VI. Our calculations of the second-order optical response for monolayer TMDs are useful for benchmarking, providing the intrinsic response, and for elucidation of trends in developing concepts for application. We analyzed the results by comparison with experimental measurements and previous computations, as available. We found that the second-order nonlinear optical properties of the monolayer TMDs are generally comparable in magnitude to other bulk materials currently in use in electro-optical devices. Given the magnitude of the second-order nonlinear optical properties and the two-dimensional nature of these materials, avenues are opening for reducing the size of electro-optical devices by using monolayer TMDs.