Effect of phonon self-energy correction on hot-electron relaxation in two-dimensional semiconductor systems

We study the phenomenon of hot-carrier relaxation via LO-phonon emission in two-dimensional semiconductor quantum wells. Calculations are done for a model in which the hot-electron gas is described by a temperature T, which is higher than the lattice temperature. In addition to including the usual dynamical screening and hot-phonon effect, we also include a phonon self-energy correction due to its coupling with the electron gas in the plasmon-pole approximation. This leads to a large enhancement of the power loss at low temperatures for low-density samples. The numerical results are in good agreement with the available experimental results.