首先把本征值方程投影到导带的子空间中,进而得到AlGaN/GaN量子阱中第一、二子带的Rashba自旋劈裂系数(α_1,α_2)和子带自自旋-轨道耦合系数η_(12).然后自恰求解薛定谔方程和泊松方程计算了不同栅压的量子阱中的α_1,α_2和η_(12),并分别讨论了量子阱阱层、左右异质结界面和垒层对它们的贡献.结果表明可以通过栅压来调节自旋-轨道耦合系数,子带间自旋轨道耦合系数η_(12)比Rashba自旋劈裂系数α_1,α_2小,但基本在同一数量级.
Rashba spin splitting coefficients for the first two subbandsα1,α2 and intersubband spin-orbit coupling coefficientη_(12) are obtained by projecting the characteristic equation into the subspace of conduction band.Then Schrodinger and the Poisson equations are solved self-consistently to calculateα_1,α_2 andη_(12) under different gate voltages.Then contributions to the spin-orbit coupling coefficients from the well,the left and the right heterointerfaces and the left and the right barriers of the quantum well are discussed. Resulsts show that the spin-orbit coupling coefficient can be modulated by the gate voltage,and the intersubband spin-orbit coupling coefficients calculated here are a little smaller than the Rashba coefficientsα_1,α_2,but they are basically of the same order.