Plasma Instability Based Compact Coherent Terahertz Radiation Sources

摘要

We explore the feasibility of plasma instabilities in quantum well structures with the aim of developing compact, coherent THz radiation sources, by introducing and studying specific structures which could lead to experimental verification of current driven plasma instabilities, and ensuing Thz radiation. A fully self-consistent formalism was developed to determine the non-equilibrium steady state under bias. Determination of the non-equilibrium steady state provides the I-V curves and the plasma response. These are in good agreement with experiments carried out at TU Vienna. A sharp emission line was obtained in the most recent structure, suggesting that we are close to the onset of plasma instability. Effects of magnetic field on the electron-electron scattering rate was studied theoretically, and experimentally verified, providing a diagnostic tool for the relative strength of two-electron, vs. one-electron scattering processes. A new connection was established with an experimental group at UC santa Barbara, to obtain an independent proof of principle of the plasma instability phenomenon in a THz pumped quantum well structure.