Electro-optical control of spin-orbit coupling in AlInAs/GaInAs single and double quantum wells

The electro-optical manipulation of the spin-orbit couplings in single and double quantum wells has been explored with the help of the external laser field and gate voltage. We focus on the situation of two-subband occupation of the wells, and obtain the Rashba (alpha(v), v=1,2 is the subband index) and Dresselhaus coefficients beta(v) by solving the coupled Poisson and Schr & ouml;dinger equations. Firstly, the laser dressing effect is demonstrated in that the laser field alters the confining potential and quantized energy levels of electrons localized in the well, in favor of flexible spin-orbit control. In combination with the gate voltage, we have realized selective control of the Rashba coupling, i.e., separately tuning alpha(v) of one subband and keeping the other unaffected. Moreover, the electro-optical manipulation can even alter the relative signs of alpha(v), making it feasible to realize skyrmion-lattice density excitation. Further, the Dresselhaus coupling, which is insensitive to the electrical manipulation, can be controlled by the laser field, greatly improving the possibility of persistent-skyrmion-lattice formation by reaching the condition of alpha(1)=beta(1 )and alpha(2)=-beta(2). These diverse SO behaviors under the electro-optical manipulation should simulate experiments for exploring promising applications in novel spintronic devices.