Spin coherence enhanced by in-plane electric field-induced spin-orbit interaction

We investigated the dependence of spatial spin distribution on bias voltage in a GaAs quantum well with Kerr rotation microscopy. The spin precession frequency of drifting spins depends on in-plane electric fields, which indicates that effective magnetic fields induced by spin-orbit interactions are modulated by in-plane electric fields. By comparing an experimental result and a theoretical simulation based on the Monte Carlo approach, we confirmed that the in-plane electric field dependence of effective magnetic fields can be attributed to the k-cubic term of the Dresselhaus spin-orbit interaction. We found that spin coherent length can be elongated by balancing a Rashba SOI and all the terms of a Dresselhaus spin-orbit interaction. This technique will provide a new way of both suppressing spin relaxation and controlling the spin precession frequency when using the cubic Dresselhaus SOI.