Ring-shaped luminescence patterns in a locally photoexcited electron-hole bilayer

摘要

We report the results of molecular dynamics simulation of a spatiotemporalevolution of the locally photoexcited electrons and holes localized in twoseparate layers. It is shown that the ring-shaped spatial pattern ofluminescence forms due to the strong in-layer Coulomb interaction at highphotoexcitation power. In addition, the results predict (i) stationary spatialoscillations of the electron density in quasi one-dimensional case and (ii)dynamical phase transition in the expansion of two-dimensional electron cloudwhen threshold electron concentration is reached. A possible reason of theoscillations and a theoretical interpretation of the transition are suggested.