Publication: Fabrication of femtosecond laser written depressed-cladding waveguides in Tm3+:BaY2F8 crystal and laser operation near 2 μm
Program
KU-Authors
KU Authors
Co-Authors
Tonelli, Mauro
Advisor
Publication Date
2022
Language
English
Type
Journal Article
Journal Title
Journal ISSN
Volume Title
Abstract
To our knowledge, we report the first waveguide laser operation of Tm3+:BaY2F8 crystal near the wavelength of 2 mu m. Femtosecond laser inscription was employed to fabricate two waveguides, each in the form of a circular depressed cladding, with diameters of 30 mu m and 50 mu m. For the 50-mu m-diameter waveguide, the propagation loss was determined as 0.22 dB/cm at the wavelength of 731 nm. A two-mirror resonator consisting of a buttcoupled input high reflector and a 10-cm-radius curved output coupler housed the Tm3+:BaY2F8 crystal waveguide during lasing experiments. By using a continuous-wave Ti3+:sapphire laser at 781 nm, waveguide lasing was obtained at 1.86 mu m. By using a 6% output coupler, as high as 73 mW of output power was obtained with the 50-mu m-diameter waveguide at an incident pump power of 680 mW, corresponding to a slope efficiency of 13.1%. Lasing threshold pump powers as low as 23 mW were further achieved with a 2% output coupler by using the 30-mu m-diameter waveguide. These results show that the Tm3+:BaY2F8 crystal possesses an important potential in the development of compact, efficient, femtosecond laser written waveguide lasers near 2 mu m.
Description
Source:
Optical Materials
Publisher:
Elsevier
Keywords:
Subject
Materials science, Optics