Abstract-Controlling Amplitude and Radiation Pattern of Emitted Terahertz by Group Velocity Mismatch

 H. Sobhani, H. Zakeri-Khatir, A. Shekari Firouzjaei,

https://ieeexplore.ieee.org/document/8408828/

In this paper, effect of group velocity mismatch on the characteristic of terahertz radiation from a plasma irradiated by two color laser pulses is investigated. The group velocity mismatch is directly related to the slippage-limited interaction length. In order to control the characteristic of generated terahertz radiation, the slippage-limited interaction length effect on radiation pattern and electric field amplitude is investigated. The slippage-limited interaction length can be controlled by the background plasma density. By rising the plasma density, the slippage-limited interaction length is decreased. Consequently, the terahertz electric field amplitude is reduced and the radiation pattern is modified. In addition, by tuning the plasma density, the power pattern directivity and the side lobe level are controlled.