ON THE DOUBLY RESONANT DIFFERENCE-FREQUENCY MIXING IN AN ASYMMETRIC QUANTUM-WELL STRUCTURE

The effect of the depolarization field on the doubly resonant frequenc y mixing due to resonant intersubband transitions in asymmetric quantu m wells, with only the ground subband occupied, is discussed. Calculat ions are performed in the framework of the perturbative density matrix formulation with relaxation time approximation. The results show that in the considered system the depolarization effect can be included by simple replacement (in the one-electron expression for the nonlinear susceptibility) of the intersubband energy by the depolarization shift ed intersubband energy. (C) 1995 American Institute of Physics.