Chinese Optics Letters, 2021, Vol. 19, Issue 3, pp.
Efficient generation of third harmonics in Yb-doped femtosecond fiber laser via spatial and temporal walk-off compensation [Early Posting]
Zhang Meng, Chu Yuxi, Zhao Jun, Yan Dongyu, Li Yongzhi, Bi Genyu, Liu Bowen, Hu Minglie
- Ultrafast Laser Laboratory, Key Laboratory of Opto-electronic Information Science and Technology of Ministry of Education, School of Precision Instruments and Opto-electronics Engineering
- Tianjin University
On the basis of a home-made femtosecond Yb-doped fiber laser, we designed a compact and efficient third harmonic generation scheme by a simple compensation plate of β-BaB2O4 (BBO) crystal. The compensation plate is optimized through its thickness and cutting angle to reverse both spatial and temporal walk-off. By optimizing the parameters of the compensation plate and incident light intensity, a maximum output of 2.23 W with a repetition rate of 1 MHz at 345 nm is obtained, which implies a conversion efficiency of 23% from infrared to ultraviolet (UV).