Theoretical Analysis of Microwave-Generation in Semiconductor Multiple Quantum Well Structures

We present a theoretical analysis of different aspects associated with the microwave generation due to charge oscillations in an asymmetric double quantum well structure. The generation of the electron wave packet is described in terms of a multiband version of the semiconductor Bloch equations. The signal decays due to carrier-carrier and carrier-phonon scattering processes, which are taken into account by a microscopic model. Coherent phonons lead to a density dependent frequency shift.