Beating of dark hollow laser beams in magnetized plasma under the influence of D.C. electric field to generate THz radiation

Abstract

In the present theoretical analysis, a new scheme of terahertz (THz) generation is proposed by beating of the two dark hollow laser beams (DHLBs) in the magnetized plasma under the influence of a D.C. electric field. The D.C. electric and static magnetic fields are applied mutually perpendicular to each other as well as to the direction of propagation of DHLBs. The nonlinear current density becomes strong due to the coupling between the nonlinear density and D.C. drift velocity of the electrons of magnetized plasma which is further responsible for THz generation. The normalized THz amplitude shows enhancement with the increase of D.C. electric and static magnetic fields. The dark-size parameter and beam order also play a significant role in the enhancement of the THz generation. The present scheme is capable of generating THz radiation at laser intensities \( \ \,10^{14} \;{\text{W}}/{\text{cm}}^2\), the magnetic field \( 38\;{\text{kG}}\), D.C. electric field \(45\;{\text{kV}}/{\text{cm}},\) and electron temperature \(\ \,6\;{\text{keV}}.\) We have also considered the mutual interactions between the DHLBs and emitted THz radiation with magnetized plasma to provide more practical and accurate results. This scheme can be proved to be very effective and helpful in developing a proper tunable THz source for the investigation of histopathological samples, Bessel cell carcinoma tissues, and the treatment of tumors.