Numerical Simulation of Plasma Oscillation in 2-D Electron Gas Using a Periodic Steady-State Solver

The terahertz oscillation due to the plasma instability in the 2-D electron gas is numerically investigated using an in-house developed device simulator, G-Device. In order to overcome practical difficulties in the conventional transient simulation, a periodic steady-state (PSS) solver is implemented. The full Newton-Raphson scheme is applied to a set of discretized equations sampled at various time points during an oscillation period. Numerical results show that there is a threshold value of the injection velocity that allows the PSS oscillation. Moreover, the impact of the drain load resistance on the oscillation amplitude is estimated. It is found that considerable amplitude of the voltage oscillation can be achieved even with finite drain resistances. Although the growth rate of the voltage oscillation exhibits its maximum value with the infinite drain resistance, the maximum output power is obtained at a finite drain resistance.