Materials for Nonlinear Optics in the GHz-THz Range

This talk starts with an outline of our hybrid approach combining Nonequilibrium Green's Functions with the Boltzmann equation for the nonlinear response of semiconductor superlattices. The nonlinearities are controllable and very good agreement has been found between theory and experiments. Next, we address the efficiency of the superlattices as frequency multipliers and their feasibility for room temperature THz radiation sources based on multiplication of GHz inputs.