Abstract

The amount of optical second harmonic generated in a centrosymmetric medium in the presence of a dc electric field depends on a convolution of the optical and dc field distributions in space. Thus, measurements of the harmonic generation associated with a known dc field distribution gives information on the optical field distribution. This method has been used to investigate the focal region of a laser beam. It avoids difficulties with resolution and probe damage that arise when conventional methods are used near the focus. The detailed data are in excellent agreement with results predicted for a pure TEM₀₀ laser beam with the notable exception that the effective confocal parameter is about a factor of 2 smaller than that indicated by conventional measurements. We believe this effect is associated with the truncation of the laser beam by the intracavity mode-selecting aperture, and indicates that dc induced second-harmonic generation constitutes a sensitive probe of experimentally interesting mode distortions.

© 1975 Optical Society of America

Laser beam characteristics using dc-induced second harmonic generation

Jayanta K. Guha
Appl. Opt. 15(10) 2381-2384 (1976)

Electric field induced second harmonic generation in glass

C. G. Bethea
Appl. Opt. 14(10) 2435-2437 (1975)

Experimental technique of dc induced SHG in liquids: measurement of the nonlinearity of CH₂I₂

C. G. Bethea
Appl. Opt. 14(6) 1447-1451 (1975)

Acoustical wave effects on the beam quality of a high energy CO electric discharge laser

G. L. McAllister, V. G. Draggoo, and R. G. Eguchi
Appl. Opt. 14(6) 1290-1296 (1975)

Propagation aspects of nonlinear optical interactions involving intersecting focused beams

John W. Dudley and J. F. Ward
Appl. Opt. 20(10) 1777-1780 (1981)