Exploring the characteristic of optical vortex beam in a self-mode-locked Yb:KGW monolithic laser

• Main Authors: Chen, Chun-Yu, 陳君昱
• Other Authors: Chen, Yong-Fu
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/2w93c5

碩士 === 國立交通大學 === 理學院應用科技學程 === 106 === In this thesis, we investigate the formation of high-order transverse mode in a Yb:KGW monolithic laser and observe the structure of the optical vortex converted by a cylindrical lens. We firstly investigate the characteristic of Yb:KGW crystal in the quasi-three-level laser system and the monolithic cavity design. We then explore the output performance and the temporal behavior of the monolithic laser. Optical vortex beam is further generated by a cylindrical lens mode convertor and the vortex structure is examined by a Mach-Zehnder interferometer. Finally, theoretical analysis is carried out to analyze the experimental results. Dual-comb self-mode-locked operation with abundance of transverse pattern along Nm- and Np-axis is experimentally obtained with high-power high-repetition-rate Yb:KGW monolithic laser. We further employ a cylindrical lens mode convertor to generate LG0,2 and LG0,3 mode and the vortex structure is successfully observed through a Mach-Zehnder interferometer. The simulation result corresponds well with the experimental result for the LG0,2 mode.