External electric field control of THz pulse generation in ambient air.
A theoretical model has been proposed to describe the dependence of the THz wave generated in a laser-induced air plasma on the external electric field. Using this model we predict the following, (i) previously observed results show that the THz pulse enhances linearly with the increase of the external field; (ii) the THz pulse varies as a cosine function with the angle between the direction of the external electric field and the polarization of the incident exciting beam; (iii) and the amplitude is proportional to the square of the intensity of the incident pulse in a low energy region. These predictions are validated by our experiment.
Sun
Wen-Feng
WF
Department of Physics, Capital Normal University, Beijing 100037, China.
Zhou
Yun-Song
YS
Wang
Xin-Ke
XK
Zhang
Yan
Y
D000388:Air; D003198:Computer Simulation; D004574:Electromagnetic Fields; D005740:Gases / Q000737:chemistry* / Q000528:radiation effects*; D006358:Hot Temperature; D007834:Lasers; D008027:Light; D008872:Microwaves; D008962:Models, Theoretical; D012542:Scattering, Radiation; D012815:Signal Processing, Computer-Assisted
D005740:Gases