Anti-Stokes luminescence in nitrogen doped GaAs_1−xP_xalloys

Abstract

In indirect band gap alloys, the Nx levels of the excitons bound to nitrogen have been resonantly excited. The detection of the photoluminescence (PL) at energies greater than the excitation energy (Anti-Stokes Luminescence (ASL)) shows a new PL band which appears at temperatures lower than 40 K. Its mean energy 2.205 eV is nearly independent of the alloy composition. We investigate ASL as a function of excitation photon energy, excitation power and temperature. Moreover ASL has been time resolved.