Magneto-transport in high mobility n-InSb/InAlSb quantum wells

The inherent large spin-orbit (SO) coupling InSb quantum wells (QWs) is expected to result in sensitive tunability of the Rashba effect with electric field. The strength of the SO coupling can be extracted from measurements of weak anti-localisation (WAL) and from the beating of Shubnikov-de Haas (SdH) oscillations [1]. We have investigated these phenomena and report magneto transport measurements from a range of InSb/InAlSb QWs with varying carrier density n and mobility μ. It is shown that the inherent large Zeeman splitting combined with inhomogeneous level broadening means that beating in the SdH oscillations in InSb QWs are rarely observed. However, her we show that in InSb/InAlSb QWs, n can be modulated using a gate electric field from 1.15Rashba effect. Extracted values of the Rashba parameter from beating [2], WAL and k.p modelling [3] is discussed. [1] V.A.Guzenko et al., PRB 76 (16), 165301 (2007) [2] G.Engels et al., PRB 55 (4), R1958 (1997) [3] A.M.Gilbertson et al., PRB 77 (16), 165335 (2008)