Numerical Investigation of the Bias Voltages Effects on the Performance of Plasmonic HEMTs

The two dimensional (2D) plasmon propagation in the channel of a high electron mobility transistor (HEMT) is numerically analyzed using the full wave method. By applying different bias voltages to the drain and the gate terminals, the properties of the 2D plasmons propagation along the channel are investigated. In this analysis, the Maxwell’s equations are solved in conjunction with the hydrodynamic transport equations, using the finite difference time domain (FDTD) technique. The obtained results show that the wavelengths and the propagation constants of the 2D plasmons are considerably affected by varying the bias voltages. Then, by considering these effects, the tunability of a grating gate HEMT detector over terahertz (THz) frequencies is investigated, using the proposed full wave model. Our studies demonstrate that it is possible to control the characteristics of the 2D plasmon propagation along the channel by changing the bias voltages to produce various types of reconfigurable structures used for THz applications.