Long-wavelength edge of the spectrum of hot electron–hole plasma radiation in photoexcited indium arsenide

Abstract

The long-wavelength edge of the radiation spectrum of hot electron–hole plasma induced in indium arsenide by neodymium laser pulses is studied. The shape of the long-wavelength edge is nearly exponential and is independent of the pump power in the range 1–2 MW/cm2. The constancy of the exponential factor indicates that the filling of LO-phonon states only slightly depends on the excitation power; i.e., the ensemble of LO phonons still does not heat up. The phonon temperature is determined and is shown to coincide with that of the crystal lattice. The absence of phonon heating is explained by strong e–h interaction and the screening of the electron energy scattering by LO phonons.