High Average Power-Green Laser for Synchronous Photoinjection

A high-quantum-efficiency long-lifetime photocathode is a key component for the synchronous photoinjection of GaAs photoemission guns, used in modern particle accelerators. High-power pulsed-laser sources, with picosecond pulse durations at GHz repetition rates, are needed to provide enough power to enable this application; yet, none are commercially available. This project will develop a highly efficient, high-average-power (~100 W) green laser source, based on second harmonic generation of a high power fiber laser, with variable pulse durations and repetition rates. This fiber-laser-based approach will provide a reliable, capable, cost-efficient, and extremely versatile laser light source to improve the performance of DOE¿s accelerators. Phase I, will design and construct an efficient front end for the laser source and demonstrate the flexibility of the high-rep-rate and short pulse waveforms. The front end will use fiber components and inline connections, with no mirrors or free-space propagation in the optical design. The front end developed in Phase I will provide enough power for the Phase II amplification and frequency conversion. Commercial Applications And Other Benefits as described by the Applicant: The high power green laser, combining high power and high brightness with low signal noise at high repetition rates, would have the potential to replace existing mode-locked DPSS lasers for medical, material processing, micromachining, semiconductor processing, and underwater communications