Determination of spin-orbit coefficients in semiconductor quantum wells

We report the determination of the intrinsic spin-orbit interaction (SOI) parameters for In0.53Ga0.47As/In0.52Al0.48As quantum wells (QWs) from the analysis of the weak antilocalization effect. We show that the Dresselhaus SOI is mostly negligible in this system and that the intrinsic parameter for the Rashba effect, aSO≡α/Ez, is given to be aSOm*/mₑ=(1.46-1.51×10^-17NS [m^-2]) e², where α is the Rashba SOI coefficient, Ez is the expected electric field within the QW, m*/mₑ is the electron effective mass ratio, and NS is the sheet carrier density. These values for aSOm* were also confirmed by the observation of beatings in the Shubnikov--de Haas oscillations in our most asymmetric QW sample.