Broadly tunable optical vortex beam in a diode-pumped Yb:CALGO laser
Lina Zhao, Ye Yuan, Luyang Tong, Fangxin Cai, W. Zhang, Yangjian Cai
Abstract
In this paper, the direct generation of vortex beams in a diode-pumped Yb:CALGO laser has been realized for the first time. The wavelength of the output vortex beam was broadly tunable from 1040 to 1086 nm by using a birefringent filter as wavelength-selecting element. The vortex beams could be maintained quite well at different wavelengths and pump powers. The maximum output power of the vortex laser in the experiment was 860mW at 1060.4 nm. The orbital angular momentums with the topological charges l = 1 and l = −1 were verified by the interferograms. Such a wavelength-tunable vortex laser can potentially be applied in high-capacity and multi-channel optical communications.