Kinetic Monte-Carlo simulation of exciton hopping: Urbach-tails in gas-molecule decorated MoSe2

We quantitatively investigate disorder parameters of gas-molecule decorated monolayer MoSe2. This material system is interesting because disorder may be introduced and removed at will by regulating the number of adsorbed gas molecules through laser annealing. These molecules electrostatically trap excitons leading to localized defect states, which are exponentially distributed in energy. Here, experiments are described by kinetic Monte-Carlo simulations, in summary enabling richer studies than within crystalline materials with a fixed degree of disorder. We find that the surface coverage of the MoSe2 may reach up to one molecule per 2nm2 and that the density of adsorbed molecules depends on the laser power by a power law.