The effect of k-cubic Dresselhaus spin–orbit coupling on the decay time of persistent spin helix states in semiconductor two-dimensional electron gases

We study the theoretical effect of k-cubic (i.e. cubic-in-momentum) Dresselhaus spin–orbit coupling on the decay time of persistent spin helix states in semiconductor two-dimensional electron gases. We show that the decay time of persistent spin helix states may be suppressed substantially by k-cubic Dresselhaus spin–orbit coupling, and after taking the effect of k-cubic Dresselhaus spin–orbit interaction into account, the theoretical results obtained accord both qualitatively and quantitatively with other recent experimental results.