Effect of Self-focused High Power Elliptical Laser Beam on Second Harmonic Generation in Unmagnetized Plasma
The present paper investigates the effect of self-focused high power elliptical laser beam on second harmonic generation in unmagnetized plasma. Non-uniform heating results in redistribution of carriers. As a result, transverse density gradient is established in plasma, which results in excitation of electron plasma wave at pump wave frequency. The electron plasma wave so generated further interacts with the pump beam to produce second harmonic. Effect of variation in laser beam intensity and plasma density on second harmonic yield is studied in detail. Second harmonic yield is found to increase/decrease with increase in plasma density/laser beam intensity.
Keywords: Self-focusing, elliptical laser beam, electron plasma wave, second harmonic yield.