Hall-effect measurements in p-type InGaAs/GaAs strained-layer superlattices

Abstract
We report, for the first time, temperature‐dependent Hall data for holes in modulation‐doped In0.2Ga0.8As/GaAs strained‐layer superlattices. Samples with (compressive) planar strains of −0.5% to −1.2% in the InGaAs quantum wells were used, providing a range of configurations for the two (overlapping) sets of valence‐band quantum wells derived from the bulk heavy‐ and light‐hole bands. All samples exhibit transfer of holes into the InGaAs quantum wells at low temperature; however, the sample with the least strain shows evidence for gradual carrier freeze‐out over a wide range of temperature.