Share Email Print

Proceedings Paper

Theoretical analysis of second harmonic characteristics generated by KTiOPO4 crystal
Author(s): Kazufumi Nomura; Etsuji Ohmura; Alexander Horn; Isamu Miyamoto
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

In the harmonic generation using nonlinear optical crystals, phase-matching technique is indispensable for obtaining high conversion efficiency. As the first step of our study, we have investigated crystal temperature variation induced by laser absorption and its influence on conversion efficiency and beam profile in second harmonic generation (SHG) by solving the coupling problem composed of heat conduction equation and complex amplitude equations. In this study, we focused on the declination of irradiation angle of laser from the phase matching angle, which is equivalent to the declination of cut angle of crystal. The influences of angle declination and temperature rise of the crystal on SHG characteristics were examined by supposing KTiOPO4 (KTP) crystal. Main results obtained are as follows: When the angle declination is only 0.1 deg, conversion efficiency easily decreases to half that under perfect phase-matching condition. Significant distortion of output beam profile of second harmonic is also caused by the angle declination. This essential problem on output beam profile should be considered in precision microfabrication. Influences of angle declination and temperature change on phase mismatching are superposed. Our analysis is useful to elucidate such compounded and complicated phenomena in frequency conversion. A possibility of cancellation of phase mismatching due to angle declination by keeping crystal temperature higher than phase matching temperature was suggested through numerical examples.

Paper Details

Date Published: 18 November 2003
PDF: 6 pages
Proc. SPIE 5063, Fourth International Symposium on Laser Precision Microfabrication, (18 November 2003); doi: 10.1117/12.540755
Show Author Affiliations
Kazufumi Nomura, Osaka Univ. (Japan)
Etsuji Ohmura, Osaka Univ. (Japan)
Alexander Horn, RWTH-Aachen (Germany)
Isamu Miyamoto, Osaka Univ. (Japan)

Published in SPIE Proceedings Vol. 5063:
Fourth International Symposium on Laser Precision Microfabrication
Isamu Miyamoto; Andreas Ostendorf; Koji Sugioka; Henry Helvajian, Editor(s)

© SPIE. Terms of Use
Back to Top