Abstract
A non-pulse-leakage optical fiber pumped 100-kHz level high beam quality Nd:YVO4 picosecond amplifier has been developed. An 80 MHz, 11.5 ps mode-locked picosecond laser is used as the seed with single pulse energy of 1 nJ. By harnessing the double β-BaB2O4 (BBO) crystal Pockels cells in both the pulse picker and regenerative amplifier, the seed pulse leakage of the output is suppressed effectively with an adjustable repetition rate from 200 to 500 kHz. Through one stage traveling-wave amplifier, a maximum output power of 24.5 W is generated corresponding to the injected regenerative amplified power of 9.73 W at 500 kHz. The output pulse duration is 16.9 ps, and the beam quality factor M2 is measured to be 1.25 with near-field roundness higher than 99% at the full output power.
Highlights
Over the past decade, there has been significant development of high power ultrashort pulse lasers with high repetition rate [1,2,3], with applications including nonlinear optical frequency conversion, precise material processing, satellite ranging, and high-intensity physics [4,5,6,7]
We tested the leakage of the regenerative amplifier by monitoring the output power with the PC2 turning on and off
The pump power of the regenerative amplifier is set to be 50 W because higher power may result in the self-excited oscillation between the M4 and M8
Summary
There has been significant development of high power ultrashort pulse lasers with high repetition rate [1,2,3], with applications including nonlinear optical frequency conversion, precise material processing, satellite ranging, and high-intensity physics [4,5,6,7]. In ultrashort lasers in the order of picoseconds, their pulse width is smaller than the electron-phonon coupling time of most materials, heat conduction can be decreased substantially during the process of interaction. When the repetition rate is up to 100 kHz, it is very difficult for the Pockels cell to realize the fast and complete switching due to the limitations of high voltage driving supply This will lead to the leakage of the directly amplified seed pulses in the output that introduce optical noise and increase unnecessary pump power consumption. To eliminate the leakage of the regenerative amplifier in high repetition rate operation, double BBO crystal Pockels cells are adopted as one switch to improve the responsivity of the switching. Our measurements show that this method effectively realizes the suppression of leakage and improves the purity of the regenerative amplified pulses
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
