Terahertz wave excitation by nonlinear coupling of intense laser field with magnetized plasma

In this article, the plasma density, the laser intensity and the external magnetic field are playing vast roles firstly to generate a coherent THz wave then to enhance the stability of generated THz. Due to the relativistic increase of electron mass, the relativistic self-focusing of a right circular polarized (RCP) laser beam inside magnetized plasma will occur which leads to raising the laser power to enough limits for exciting the terahertz wave. By fulfilling the energy–momentum conservation conditions, a terahertz wave frequency at the difference between the laser pump wave frequency and plasma wave frequency is obtained. More stabilization and higher power (reaching to tens of gigawatts) of terahertz field amplitude have been observed whenever the plasma density, the laser intensity, and the external magnetic field are increased. Better results are recorded at high THz frequency (5 THz) compared with low THz frequency (1 THz).