Rapid spin flip in a spin subband at an anticrossing region in a slightly asymmetric modulation-doped quantum well

The spin splitting due to structure and bulk inversion asymmetry is calculated for electron subbands in wide slightly asymmetric InGaSb quantum wells. At anticrossings, rapid spin flips in two steps are found as the in-plane wave vector along the [1 1] direction is increased by 0.002 nm−1. First the y-component and then the x-component is flipped. A change of bias of about 1 meV across the quantum well is sufficient move the Fermi level across the anticrossing region.