We demonstrated that transverse mode can be controlled by manipulating gain distribution in a Yb:YAG ceramic thin disk. Several elongated higher order transverse modes of a Hermite–Gaussian beam were observed when a straight-line-shaped gain region was created by using a diode laser output from an optical fiber. An orthogonally crossing pair of straight-line-shaped gain regions created with an additional optical fiber output resulted in the generation of a doughnut-shaped Laguerre–Gaussian beam. This implies that easy and quick switching of Hermite–Gaussian and Laguerre–Gaussian beams is possible without mechanical handling.
© 2011 Optical Society of America
Lasers and Laser Optics
Original Manuscript: August 17, 2011
Revised Manuscript: September 20, 2011
Manuscript Accepted: September 20, 2011
Published: October 19, 2011
Koki Shimohira, Yuichi Kozawa, and Shunichi Sato, "Transverse mode control by manipulating gain distribution in a Yb:YAG ceramic thin disk," Opt. Lett. 36, 4137-4139 (2011)