Attenuation Characteristics of Terahertz Electromagnetic Wave in Nonuniform Plasma Slab

The propagation of terahertz electromagnetic wave in plasma is discussed. The attenuation and phase shift for the unmagnetized plasma slab can be modeled. The proposed formulas show that wave attenuation and phase shift in unmagnetized plasma depend on the collision frequency, wave frequency, plasma density and plasma thickness. Comparisons of terahertz wave attenuations by proposed models, Z- Transform Finite Difference Time Domain (ZT FDTD) method, Jamison et al.'s formula and experimental results show good agreement in uniform unmagnetized plasma. In nonuniform unmagnetized plasma, obtained results of the wave attenuation by proposed formula are compared with those obtained by WKB method. It is found that terahertz wave attenuations by our model and WKB method show good agreement.