Modulational instability characteristics for few cycle pulse propagation in cascaded-quadratic-cubic-quintic nonlinear media

Using phase amplitude ansatz method and standard linear stability analysis, we have investigated modulational instability (MI) for the ultrashort pulse propagation in cascaded quadratic-cubic-quintic nonlinear media. Propagation of wave has been described beyond the slowly varying envelope approximation (SVEA). Controlling the generation of frequency side-bands and hence desired pulse, through engineering of different parameters are being explored.