Transport effects in remote-doped InSb/AlxIn1-xSb heterostructures

Low- and high-field magnetotransport measurements on two 30 nm δ-doped InSb/AlInSb quantum wells (QWs) with different doping densities are reported. The QW two-dimensional electron gas (2DEG) carrier densities and mobilities were extracted by analysis of the Hall and quantum Hall data, mobility spectra and Shubnikov-de Haas oscillations. 2DEG channel mobilities of up to 324 000 cm2 V-1 s-1 (T=2 K) and 44 000 cm2 V-1 s-1 (T=300 K) are extracted. Carrier densities and mobilities for transport parallel to the 2DEG layer are also deduced where observable. The importance of thermally generated carriers in the lower AlInSb barrier material and the role of transport within the δ-doping plane is considered and the total carrier population as a function of temperature of the two samples is deduced, which is in excellent agreement with experimental observation.