Third harmonic in propagation of intense laser pulse in quantum magnetoplasma

The interaction of intense short laser pulse with plasma leading to harmonic generation has been an active area of research in the recent years. The propagation of high intensity laser pulse has been investigated in various plasma conditions. Plasma where the density is quite high and the de-Broglie thermal wavelengths associated with the charged particle approaches the electron Fermi wavelength and exceed Debye radius, degeneracy comes into picture and the study of quantum effects become important. The high-density, low-temperature 'quantum Fermi plasma' is significantly different from low-density, high-temperature 'classical plasma'. The field of quantum plasma has attracted attention of physicists due to its wide range of applications in modern technology. In the present paper, the propagation of circularly polarized laser beam through magnetized quantum plasma has been studied and generation of third harmonic has been analyzed. The interaction dynamics has been built, using the quantum hydrodynamic (QHD) model. The QHD model consists of a set of equations describing the transport of charge, momentum and energy in charged particle system interacting through a self consistent potential. The effects of quantum Bohm potential, electron Fermi statistical pressure and electron spin have been incorporated. The excitation of third harmonics by circularly polarized laser pulse in magnetized quantum plasma is presented. The field amplitude of third harmonic radiation has been calculated and compared to the fundamental amplitude of the incident radiation. It is found that quantum effects enhance to the third harmonic radiation generation. (author)