The Propagation Characteristics of Terahertz Wave in a DBD Plasma

High density plasma diagnostic is a challenging task because of its high electron density. Dielectric barrier discharge (DBD) plasma is one of the typical high density plasmas, which has widespread applications because of its unique characteristics. However, its diagnosis is the key to develop new applications. In this paper, we analyze the propagation characteristics of terahertz wave in a DBD plasma (Figure 1) with numerical simulation and experiments. The finite-difference time-domain (FDTD) method is used to calculate the transmission characteristics of broadband terahertz wave in a modeling DBD plasma. In addition, the propagation of terahertz wave with a broad frequency from 0.5 THz to 3 THz in a DBD plasma is studied experimentally by the terahertz time-domain spectroscopy (THz-TDS) technology. The results develop a new idea for the terahertz diagnostic of plasma with high density.