Behaviours of excitonic optical nonlinearity associated with a large detuning ra

The third-order optical nonlinear susceptibility χ(3) responsible for phaseconjugatebeam in non-degenerate four-wave mixing for a biased asymmetric coupledquantum well (ACQW) structure are given by the doubled-side Feynman diagram technique.It is shown that the photonic echo (PE) in exce