Optical detection of zero-field spin precession of high mobility two-dimensional electron gas in a gated GaAs/AlGaAs quantum well

Direct imaging of gate-controlled persistent spin helix state in a modulation-doped GaAs/AlGaAs quantum well

“…To adjust both Dresselhaus and Rashba SOIs such that they are equal in magnitude, applying an external electric field to control SOI fields is necessary. The Rashba SOI has been controlled by a gate electric field, [15][16][17] and a gate-controlled PSH state was demonstrated in InGaAs QWs. 18) However, direct imaging of the formation of PSH state under gate control has not been demonstrated.…”

“…The PSH state is likely to form at V g = ¹0.2 V. We can eliminate the possibility that the increase in scattering rate when carrier concentration is reduced is responsible for the observed V g dependence of ¸s. Note that 2DEG mobility is reduced when carrier concentration decreases due to the enhanced impurity and/or electron-electron scattering frequency, 17,20) which suppresses DP spin relaxation. 3) If this reduced spin relaxation is the only mechanism responsible for the gate-voltage dependence of ¸s, this dependence is expected to be monotonic.…”