Dispersion measurements of hot holes in quantum wells

An optical method for obtaining the valence subband dispersion of GaAs/AlGaAs quantum wells, including warping, is reviewed. Utilizing the recombination of hot electrons at neutral acceptors, the method gives meV accuracy. The dispersion has been measured for quantum wells with widths ranging from 3.3 nm to 9.8 nm. Measurements have been made for wavevectors from zero to greater than 10% of the Brillouin zone, corresponding to holes with as much as 50 meV of kinetic energy. The measurements are in excellent agreement with k.p calculations.