Third-order Non-linear Optical Susceptibilities in Diffusion Modified AlxGa1-xN/GaN Single Quantum Well

In this work, the variation of optical properties in the AlGaN/GaN quantum well after thermal annealing is studied. The potential profile change of the quantum well resulting from the interdiffusion of Ga and Al atoms across the interface of the well and the barrier during the thermal treatments is assumed to follow Fick's law. The results show that the thermal annealing can induce an increase of the optical susceptibilities in the AlGaN/GaN quantum well. However the third-order nonlinear optical susceptibilities are red shifted with increasing in diffusion lengths.