Rashba spin splitting in the Al0.3Ga0.7N/GaN heterostructure under uniaxial strain

By solving the Schrödinger and Poisson equations self-consistently, changes of the Rashba spin splitting for the Al_0.3Ga_0.7N/GaN heterostructure under uniaxial strain are calculated, and electrons are found to take up the first two subbands. The additional polarization induced by the uniaxial strain leads to a great enhancement of the built-in electric field and the 2DEG concentration. The Rashba spin splitting almost increases linearly with the uniaxial strain, and its amplitude increases by 36% with a strain of 4×10⁻³. The effect of electrons occupying more than one subband on the Rashba spin splitting is discussed. Results show the internal electric field caused by the polarization is crucial for the considerable Rashba spin splitting in the Al_0.3Ga_0.7N/GaN heterostructure and the magnitude of the Rashba spin splitting can be greatly modulated by the uniaxial strain, which would benefit further research and application of spintronics.