The role of defects in lowering the effective polariton temperature in electric and optically pumped polariton lasers

摘要

The role of dislocations and defects in the material constituting the active region of an exciton-polariton laser has been examined and elucidated in the context of dynamic condensation and the temperature of the lower polariton condensate, T_(LP). For a GaN microcavity diode polariton laser operated at room temperature and characterized in this study, the value of T_(LP) obtained from analysis of measured occupation in momentum space is 270 K, which is lower than the lattice temperature. Similar results from other room temperature GaN devices and GaAs-based polariton lasers operated at cryogenic temperatures are presented and discussed.