The light-hole mass in a strained InGaAs/GaAs single quantum well and its pressure dependence

Abstract The pressure dependence of the light-hole mass in a compressively strained In 0.20 Ga 0.80 As / GaAs single quantum well has been deduced from the temperature dependence of Shubnikov-De Haas oscillations over a pressure range from 0 to 15 kbar. The sample was grown by MBE on a GaAs substrate. Low temperature hole densities in the well were (3.64 ± 0.03) × 10 11 cm −2 independent of pressure. The mass of (0.156 ± 0.005)m 0 measured at atmospheric pressure agrees well with cyclotron resonance measurements reported elsewhere. The effective mass did not increase with pressure as expected but appeared to decrease between 0 and 8 kbar. It then remains constant with increasing pressure up to 15 kbar. Details of the experimental results are described and compared with theoretical calculations using a second-order 8-band k·p model. This predicts a mass which increases with pressure at a rate of about 0.5% kbar −1 in disagreement with our experimental results. The importance of the warping of the valence band and the limitations of the model are described.