Theoretical analyses and configuration optimizations of a LD-pumped 3.9 µm Ho:BYF laser. (April 2022)

• Record Type: Journal Article
• Authors: Zhang, Ying; Ma, Chaoqun; Guo, Jiawei; Rong, Kepeng; Cai, He; Han, Juhong; An, Guofei; Wang, You
• Is Part Of: Optics & laser technology. Volume 148(2022)
• Publication Date: 2022-04
• Subjects: Mid-infrared laser -- Ho:BYF -- Directly pumping -- Finite element method; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2021.107769
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: A 3.9 μm lasing was achieved through a Ho: BYF crystal directly pumped by LDs. The kinetic and thermal processes were investigated for a LD-pumped Ho:BYF laser. The maximum energy of 1.87 mJ was finally achieved after the optimization of structural parameters. Abstract: In this paper, we introduced the theoretical simulation results of output performances for a LD-pumped 3.9 µm Ho:BYF laser by considering two unique kinetic processes named as energy transfer up-conversion (ETU) and cross relaxation (CR). The influence of the pump energy, pump beam waist radius, pump pulse width, and crystal length on the output characteristics was discussed in detail for the Ho:BYF laser. The thermal simulation was also carried out for the Ho:BYF crystal by using a finite element method (FEM). Then, we constructed a LD-pumped experimental system and successfully realized a LD-pumped 3.9 µm laser. Next, some efforts were undertaken for optimizing the curvature radius of an output coupler (OC), focus position inside Ho:BYF bulks, and crystal length, respectively. The maximum energy of 1.87 mJ had been finally obtained after the optimization. By considering the LD-pumped solid-state laser is still rare in the mid-infrared, our study is thought to be useful for the development of a novel compact and efficient laser in the future.