Abstract
Resonant self-focusing, which occurs in beat-wave excitation of electron plasma waves, is crucial both for multiline laser fusion and for beat-wave accelerators. In this paper, the resonant self-focusing effect of a dual-frequency laser beam or two laser beams with frequency difference equal to the plasma oscillation frequency in a homogeneous plasma has been studied theoretically, for the first time, by using optical mixing and the self-focusing theory. The nonlinear dielectric constant and the threshold power for resonant self-focusing have been derived analytically. The scaling laws of the threshold power with respect to laser-plasma parameters have been discussed and compared with that of usual ponderomotive self-focusing. Otherwise, the effect of the deviation from the frequency matching condition on the threshold power has also been studied. For typical underdense laser-plasma parameters, our estimation shows that the threshold power of resonant self-focusing is usually ~2 orders of magnitude less than that of normal ponderomotive self-focusing. In addition, it is also shown that a small deviation from resonance will result in a large increase in the threshold power.
© 1986 Optical Society of America
PDF ArticleMore Like This
ZHI-ZHAN XU, XIN-LIN LI, TIE-FENG XU, and JING-XIU MA
WHH1 International Quantum Electronics Conference (IQEC) 1986
N. Khelfaoui, D. Wolfersberger, G. Kugel, N. Fressengeas, and M. Chauvet
WD17 Nonlinear Guided Waves and Their Applications (NP) 2005
CURTIS R. MENYUK and K. PAPADOPOULOS
WGG22 International Quantum Electronics Conference (IQEC) 1986