Relaxation of hot holes in p-Ge

Saturated absorption of infrared radiation by p-doped Ge is treated theoretically, predicting that both the saturation intensity and the width of the probe-saturator spectrum oscillate as functions of the saturator photon energy, ?ω. The maxima occur for ?ω = n?ω_LO, where n is an integer and ?ω_LO is the zone-center LO phonon energy. The results may a lso provide the closest measurement of hole cascade relaxation times to date. The oscillations depend on theoretical estimates that the LO phonon emissions occur substantially more rapidly than other decay processes. Hence failure to observe the oscillations would belie these estimates.