High-temperature ultrafast polariton parametric amplification in semiconductor microcavities.

摘要: Cavity polaritons, the elementary optical excitations of semiconductor microcavities, may be understood as a superposition excitons and cavity photons1. Owing to their composite nature, these bosonic particles have distinct response, at same time very fast highly nonlinear. Very efficient light amplification due polariton–polariton parametric scattering has recently been reported in microcavities liquid-helium temperatures2,3,4,5,6,7,8,9,10,11. Here we demonstrate polariton up 120 K GaAlAs-based 220 K CdTe-based microcavities. We show that cut-off temperature for is ultimately determined by binding energy exciton. A 5-µm-thick planar microcavity can amplify weak pulse more than 5,000 times. The effective gain coefficient an equivalent homogeneous medium would 107 cm-1. subpicosecond duration high efficiency could exploited high-repetition all-optical microscopic switches amplifiers. 105 polaritons occupy quantum state during amplification, realizing dynamical condensate strongly interacting bosons which studied temperature.