Spin-orbit interaction determined by antilocalization in an InSb quantum well

Abstract

The magnetoresistance at temperatures below 20 K in an $n\text{-InSb}/{\text{In}}_{0.85}{\text{Al}}_{0.15}\text{Sb}$ two-dimensional electron system is studied and described in terms of antilocalization due to quantum interference under strong spin-orbit interaction. The spin-orbit interaction coefficients are extracted by fitting the magnetoresistance data to an antilocalization theory distinguishing the Rashba and Dresselhaus contributions. A good agreement between magnetoresistance data and theory suggests a Rashba coefficient $|\ensuremath{\alpha}|\ensuremath{\approx}0.03\text{ }\text{eV}\text{ }\text{\AA{}}$ and a Dresselhaus coefficient $\ensuremath{\gamma}\ensuremath{\approx}490\text{ }\text{eV}\text{ }{\text{\AA{}}}^{3}$. A strong contribution from the Dresselhaus term leads to pronounced anisotropy in the energy splitting induced by spin-orbit interaction in the two-dimensional electron dispersion.