Spin excitation and band-narrowing in AlxGa1−xAs heterostructures

We studied the spin excitation in dependences of the applied electric field and lattice temperature (LT) via the measurements of the circularly polarized photoluminescence (CPPL) in AlxGa1−xAs heterostructures (HSs). The intensity of CPPL was found to strongly depend on the electric field applied to the HSs. The CPPL was also found to enhance with decreasing LT. It was demonstrated that the observed LT dependence might be due to the LT-dependent band-gap shift of the HS materials.