The dynamics of photoexcited electrons in GaAs and InP were studied using the transmission of 200‐fs pulses of far‐infrared radiation in the spectral range 15–100 cm−1. Kinetic traces of the infrared transmission as a function of delay between optical excitation and infrared probe show a probe‐limited decrease in transmission followed by a more gradual (0.7–2 ps) drop to a steady value, consistent with the slow return of electrons from high‐mass satellite valleys. Infrared transmission spectra, analyzed in the context of a Drude model, reveal density‐dependent electron mobilities 3–4 times below equilibrium n‐doped values. Electron‐hole collisions likely account for the lower mobility.
© 1992 American Institute of Physics
“Intervalley scattering in GaAs and InP probed by pulsed far-infrared transmission spectroscopy,” P. N. Saeta, J. F. Federici, B. I. Greene, and D. R. Dykaar, Appl. Phys. Lett. 60, 1477 (1992). doi: 10.1063/1.107276