Electron–plasmon relaxation in quantum wells with inverted subband occupation

We have considered the electron-plasmon interaction and intersubband resonance screening in a quantum well with inverted subband occupation. We show that in such a system the intersubband plasmon emission leads to an efficient deexcitation of the nonequilibrium initial state and raises the occupation of states at the lower-subband bottom. Downshift and resonance narrowing of the intersubband optical emission spectra are obtained and shown to be influenced by the process of intersubband plasmon excitation.