Particle-in-cell simulation of plasma wave excitation in two-dimensional electron gas

The excitation of plasma waves in a two-dimensional electron gas (2DEG) is an important mechanism for terahertz radiation and detection. In this paper, we verify the feasibility of simulating plasma waves in a 2DEG using particle-in-cell (PIC) method. To achieve the simulation model, the macro particles are filled in a thin layer and restrained by a strong field to prevent the motion in the normal direction. By perpendicularly launching an electron bunch onto the 2DEG, the processes of plasma wave generation, propagation, reflection, and nonlinear evolution are observed in phase space. It is found that the plasma wave spectrum coincides well with the theoretical dispersion relation.