Electro-optic modulation of solution-processed molybdenum disulfide

Abstract

Solution-processed molybdenum disulfide (MoS2) shows promise for tunable photonics and optoelectronics development. However, though scalable, it often leads to devices with inferior performance as a result of its random, discrete nature. In this study, we show via density-functional-theory calculations that the electronic structure of the individual solution-processed nanosheets can be modulated collectively by external electric fields. Particularly, the nanosheets can form Stark ladders, giving variations in the underlying optical processes and thus tunable collective optical properties. We confirm this electro-optical modulation experimentally using solution-processed MoS2 films with ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)] incorporated, and prove that the local polarization fields from P(VDF-TrFE) can modulate the collective optical properties of the MoS2, specifically, the optical absorption and photoluminescence. Given the scalability of solution processing, our results underpin the potential of electro-optical modulation of solution-processed MoS2 for tunable photonics and optoelectronics development. To illustrate this potential, we demonstrate solution-processed electroabsorption modulators.