Open AccessGeneration of vortex beams from lasers with controlled Hermite- and Ince-Gaussian modes
Author(s) -
Takayuki Ohtomo,
Shu Chun Chu,
Kenju Otsuka
Publication year - 2008
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.16.005082
Subject(s) - optics , laser , optical vortex , vortex , physics , beam (structure) , optical axis , gaussian beam , laser diode , diode , light beam , laser beam quality , materials science , optoelectronics , laser beams , lens (geology) , thermodynamics
We report selective excitations of higher-order Hermite-Gaussian and Ince-Gaussian (IG) modes in a laser-diode-pumped microchip solidstate laser and controlled generation of corresponding higher-order and multiple optical vortex beams of different shapes using an astigmatic mode converter (AMC). Simply changing the pump-beam diameter, shape, and lateral off-axis position of the tight pump beam focus on the laser crystal within a microchip semispherical cavity can produce the desired optical vortex beams in a well controlled manner. Pattern changes featuring different IG and HG modes obtained by rotating the AMC are also demonstrated. Numerical simulation shows that the vortex structure is changed by controlled off-axis laser diode pumping, which could lead toward precise optical manipulation of small particles.