Effect of self-focusing of elliptical laser beam on second harmonic generation in collisionless plasma

In the present paper, effect of self-focusing of elliptical laser beam on second harmonic generation is investigated in collisionless plasma by making use of paraxial ray approximation. There is redistribution of carriers from high field region to low field region by ponderomotive force and hence transverse density gradient gets established in plasma. This transverse density gradient in turn generates the electron plasma wave at pump wave frequency. The electron plasma wave so generated interacts with pump wave there by producing second harmonic. Effect of variation in laser beam intensity and plasma density on second harmonic yield is also analyzed.