Low-temperature transport properties of InSb films on GaAs(1 0 0) substrates

Low-temperature magnetoresistance (MR) has been studied for undoped and Sn-doped InSb thin films grown on GaAs(1 0 0) substrates by MBE. Sn-doped films show the Shubnikov–de Haas oscillations which reflect a large g-factor (g∗∼−40 depending on the carrier concentration) of electrons in InSb films. In undoped films, on the other hand, almost whole carriers fall into the accumulation layer at the InSb/GaAs interface at low temperatures, resulting in the advent of positive MR arising from the two-dimensional weak anti-localization due to spin–orbit interaction.