Full Article: PDF
Scientific Object Identifier: http://s-o-i.org/1.1/TAS-12-80-26
DOI: https://dx.doi.org/10.15863/TAS.2019.12.80.26
Language: English
Citation: Jasim, A. R., & Hassan, M. B. (2019). Generation of terahertz field by nonlinear interaction between laser beam and plasma. ISJ Theoretical & Applied Science, 12 (80), 136-144. Soi: http://s-o-i.org/1.1/TAS-12-80-26 Doi: https://dx.doi.org/10.15863/TAS.2019.12.80.26 |
Pages: 136-144
Published: 30.12.2019
Abstract: The study is a theoretical and simulator study of nonlinear ponderomotive force interaction between RCP laser beam TEM00 and collisionless longitudinal magneto plasma in paraxial region and nonparaxial region. The study includes two important phenomena resulted from the above interaction, which are self-focusing of laser beam and THz radiation generation. Also discussed the behavior of these phenomena at different values of initial laser beam radios and initial plasma density. The aim of study reaches to the physical and mathematical diversion for the equation of self-focusing in paraxial and nonparaxial regions. and diverting the equation of THz radiation propagation through the magneto plasma. The self-focusing in both regions (paraxial and nonparaxial) becomes faster and stronger when the initial laser beam radius is increased. The self-focusing in both regions (paraxial and nonparaxial) becomes faster and stronger when the initial Plasma frequency is increased stability is proportional with initial radios beam in both, paraxial and nonparaxial regions without apparent high increase in its amplitude. The stability of THz is higher in nonparaxial than in paraxial region. THz stability is reversely proportional with initial plasma frequency in both, paraxial and Nonparaxial regions without apparent high increase in its amplitude. In this study, Nd:YAB with wavelength of ??=1.06 ????, intensity of 10 14 ??/ ???? 2 and pulsed laser is exerted on hydrogen plasma to interact nonlinearity. The following set of parameters has been used in the numerical calculations: Laser intensity 10 14 ??/ ???? 2 . Initial beam radius ?? 0 = 2.4,2.6,2.8 ????. Laser wavelength ??=1.06 ????. Laser frequency. ?? 0 =1.778?? 10 15 ??????/??. Initial plasma frequency. ?? 1 =(0.8,0.84,0.88 ?? 0 ) ??????/??. Applied magnetic field B0=60 KG
Key words: Laser Beam; Magnetized Plasma; Rippled Plasma; Terahertz Generation; ponderomotive force; Nonparaxial region; Paraxial region; self focusing.
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