PHASE-MATCHED 3RD-HARMONIC GENERATION OF LASER-RADIATION IN A PLASMA CHANNEL - NONLOCAL EFFECTS

A laser beam propagating through a plasma channel produces density osc illations at the second harmonic. The density oscillations in conjunct ion with the oscillatory velocity at the fundamental produce third har monic current density, driving the third harmonic wave. The presence o f a background density perturbation accounts for phase matching. (C) 1 998 Published by Elsevier Science B.V.