An investigation of the recombination radiation from the electron-hole condensate in intrinsic silicon

Recombination radiation from free excitons and electron-hole droplets in high-purity silicon has been investigated in the temperature range 4.9 to 14.1K using 50 keV electron excitation. The spectra have been analysed to yield the temperature dependence of the density of electron-hole pairs, the sum of the electron and hole Fermi energies, the condensation energy and the chemical potential, and values have been obtained for the ground-state energy of the electron-hole condensate and the sum of the exchange and correlation energies. This is the first experimental determination of the temperature dependence of the electron-hole droplet parameters. The extrapolated zero-temperature values are in reasonable agreement with other experimental determinations and theoretical calculations.