Optical absorption coefficients dependence on well parameter of a coupled quantum well

The influence of the tunable well parameters on the optical absorption coefficients is theoretically studied in a coupled quantum well structure. It is shown that the transition matrix elements and the energy level differences will depend on the well parameters, which further induces the nonlinear absorption coefficients greatly enhancing. Importantly, the total absorption coefficients greatly increase because the inversion symmetry of the coupled quantum well was broken by adjusting well parameters. Moreover, with the incident laser intensity increasing, the total absorption coefficients will gradually decrease, finally resulting in the bleaching effect