Numerical Simulation of Plasma Waves in High-Electron-Mobility Transistors Using Kinetic Transport Model

We study plasma waves in a high-electron-mobility transistor (HEMT) structure by numerical simulation using the kinetic electron transport model. We find that the plasma waves in the gated section of the channel can damp even without the electron collisions with impurities and phonons. The damping is related to the thermal spread of the electron velocity. We also show that the ungated sections of the channel play an important role in determining the plasma frequency and the damping rate because the plasma waves spread over the entire channel.