Tubular depressed cladding waveguide laser realized in Yb: YAG by direct inscription of femtosecond laser

Wenlong Tang (1, 2) , Wenfu Zhang (1) , Xin Liu (1, 2) , Shuang Liu , Razvan Stoian (3) , Guanghua Cheng (1)

1 Xi’an Institute of Optics and Precision Mechanics
2 CAS - Chinese Academy of Sciences [Changchun Branch]
3 LHC - Laboratoire Hubert Curien

We report on the fabrication of tubular depressed cladding waveguides in single crystalline Yb: YAG by the direct femtosecond laser writing technique. Full control over the confined light spatial distribution is demonstrated by the photoinscription of high index contrast waveguides with tubular configuration. Under optical pumping, highly efficient laser oscillation in depressed cladding waveguide at 1030 nm is demonstrated. The maximum output power obtained is 68mW with a slope efficiency of 35% for an outcoupling transmission of 50%. A slope efficiency as high as 44% is realized when the coupling output ratio is 91% and a low lasing threshold of 70mW is achieved with the output coupling mirror of 10%.

Keywords: waveguides; laser materials processing; integrated optics devices

Domains: Engineering Sciences [physics]; Optics / Photonic

Wenlong Tang, Wenfu Zhang, Xin Liu, Shuang Liu, Razvan Stoian, et al.. Tubular depressed cladding waveguide laser realized in Yb: YAG by direct inscription of femtosecond laser. Journal of Optics, 2015, 17 (10), pp.105803. ⟨10.1088/2040-8978/17/10/105803⟩. ⟨ujm-01260815⟩