Numerical simulation of ultraviolet picosecond Ce:LiCAF laser emission by optimized resonator transients

We perform numerical simulations to investigate the spectro-temporal evolution of broadband ultraviolet (UV) laser emission from Ce:LiCAF, modeled as a system of two homogeneous broadened singlet states, using the resonator transient method. Results show that a short-pulse Ce:LiCAF UV laser emission can be achieved by choosing a cavity with the appropriate photon cavity lifetime and by controlling the pump energy. Numerical simulations were performed to determine the optimum Q-value and cavity length that will make the photon cavity lifetime small compared to the pump pulse duration. A single 31.5 ps laser pulse with about 10 µJ output energy can be generated in principle from a 1 mm, 1 mol % Ce3+-doped LiCAF crystal using a low-Q (30% output coupler reflectivity), short cavity (2 mm cavity length) oscillator pumped by 75 ps laser pulses and 140 µJ pump energy. With these transient cavity parameters, a slope efficiency of about 10% is feasible. This technique can be extended to other fluoride-based solid-state laser gain media.