Nonlocal optical properties in AlGaAs/GaAs coupled quantum well nanostructures

Nonlocal intersubband optical absorption properties in AlGaAs/GaAs coupled quantum well (CQW) nanostructures are investigated for a p-polarized light in the case of taking spatial nonlocality of optical response into account. The numerical results show that the spatial nonlocality of optical response can lead optical spectrum lines to have a radiation shift due to the nonlocal effects, and the spatial nonlocality is associated closely with the coupling effects between the potential wells of the CQW system. The dependence of the radiation shift on structure parameters of the CQW is clarified. It is also demonstrated that the maximal radiation shift and the least optical absorbance can be obtained by optimizing structure parameters of the CQW. These results may be constructive in designing nanomaterials with various nonlocality and observing the spatial nonlocal effects in experiment.