Spin-orbit-induced correlations of the local density of states in a two-dimensional electron gas

Abstract

We study the local density of states (LDOS) of two-dimensional electrons in the presence of spin-orbit (SO) coupling. Although SO coupling has no effect on the average density of states, it manifests itself in the correlations of the LDOS. Namely, the correlation function acquires two satellites centered at energy difference equal to the SO splitting, 2ωSO, of the electron Fermi surface. For a smooth disorder the satellites are well separated from the main peak. Weak Zeeman splitting ωZ ≪ ωSO in a parallel magnetic field causes an anomaly in the shape of the satellites. We consider the effect of SO-induced satellites in the LDOS correlations on the shape of the correlation function of resonant-tunneling conductances at different source-drain biases, which can be measured experimentally. This shape is strongly sensitive to the relation between ωSO and ωZ.

Spin filtering through a single impurity in a GaAs/AlAs/GaAs resonant tunneling device

“…[3][4][5] The 0D state can also be used to investigate the properties of the surrounding contacts, revealing local density of states ͑LDOS͒ fluctuations, 6,7 Landau-level ͑LL͒ formation, 8 or Fock-Darwin quantization. 9 The LDOS is also expected to carry information on the spin-orbit coupling 10 and spin lifetime. 11 In this Rapid Communication, we demonstrate that a single impurity in a barrier filters the electron spins which tunnel from a two-dimensional electron gas ͑2DEG͒ when a magnetic field is applied.…”