Investigation of Excitonic Gates in Organic Semiconductor Thin Films

Exciton gates, with an asymmetry in forward and reverse rates of energy transfer, are a means to overcome the diffusive and subdiffusive nature of exciton transport in organic semiconductors. The impact of multiple gating interfaces on exciton transport must be studied, though, to inform application of such gates in devices. Here a molecular site imbalance is engineered to establish gates, and the impact on exciton transport is examined by optically injecting excitons and detecting those that migrate through the structure. This work offers insight into the design of organic optoelectronic devices based on exciton gates, for $e.g.$ planar heterojunction photovoltaic cells.