Dresselhaus spin-orbit interaction in the -AlGaAs/GaAs/AlGaAs structure with a square quantum well: Surface acoustic wave study

The effect of spin-orbit interaction was studied in a high-quality -AlGaAs/GaAs/AlGaAs structure with a square quantum well using acoustic methods. The structure grown on a GaAs (100) substrate was symmetrically doped with carbon on both sides of the quantum well. Shubnikov-de Haas-type oscillations of the ac conductance of two-dimensional holes were measured. At a low magnetic field  T, conductance oscillations undergo beating induced by a spin-orbit interaction. Analysis of the beating character made it possible to separate the conductance contributions from the two heavy-hole subbands split by the spin-orbit interaction. For each of the subbands the values of the effective masses and quantum relaxation times were determined, and then the energy of the spin-orbit interaction was obtained. The quantum well profile, as well as the small magnitude of the spin-orbit interaction, allowed us to conclude that the spin-orbit splitting is governed by the Dresselhaus mechanism.