Picosecond carrier dynamics and studies of Auger recombination processes in indium arsenide at room temperature

Pump-probe midinfrared spectroscopic experiments with 10-ps resolution have been performed in ultrathin (0.09–3.3 μm) undoped molecular-beam epitaxy InAs epilayers on GaAs substrates near and above the fundamental absorption edge (hν=0.335–0.485 eV). Significant bleaching due to a dynamic Moss-Burstein effect was seen near the excitation photon frequency. Bleaching recovery times in the range 3000–35 ps were found, and were strongly dependent on the pump photon energy, InAs epilayer thickness, and irradiation dose in the case of layers implanted with high-energy protons. The measured evolution of the excess carrier distributions as a function of delay after excitation allowed the coefficient for Auger recombination in InAs to be measured as 1.1±0.1×${10}^{\mathrm{-}26}$ ${\mathrm{cm}}^6$ ${\mathrm{s}}^{\mathrm{-}1}$. The carrier recombination rates were found to be governed by the Auger effect for ‘‘thick’’ (>0.5 μm) samples and by a recombination velocity of ≊2.7×${10}^4$ cm ${\mathrm{s}}^{\mathrm{-}1}$ at the dislocated InAs/GaAs heterointerface for ‘‘thin’’ (