Microwave Modeling of Active Nanoelectron System with Random Imperfections

Giant quantum dot (GQD) is proposed as a resonator for a semiconductor laser. GQD is a mesoscopic quantum electron billiard filled up with active medium. To study the influence of random imperfections on spectral resonator properties we used the modeling approach based on a quasi-optical cavity resonator at millimeter wave range. We found out that random imperfections lead to the widening of resonance lines. This widening affects mainly on nearest spectral lines. The solitary lines are subjected a little to the influence of imperfections and keep high quality factor. As a result we have so-called "rarefaction" of resonator frequency spectrum due to random imperfections. The widening of resonance lines and spectrum rarefaction take place due to intermode field scattering by imperfections. We studied experimentally the generation effect in a quasi-optical cavity resonator with point-contact Gann diode at millimeter wave range. We obtained the generation both in an empty resonator and the resonator with random imperfections. The spectrum rarefaction due to imperfections leads to the reducing of resonance lines with quite high quality factor. As a result the unstable multi-frequency generation vanishes near the excitation threshold. And monocharomatic generation in the resonator has high stability at the significant exceed of the excitation threshold