Generation of 15-nJ pulses from a highly efficient, low-cost multipass-cavity Cr[superscript 3+]:LiCAF laser

Abstract

We describe the generation of enhanced pulse energies using a multipass-cavity (MPC) Cr[superscript3] +:LiCAF laser, pumped by inexpensive, single spatial mode laser diodes. A semiconductor saturable absorber was used for stable mode-locked operation. The MPC reduced the pulse repetition rate to the ~10 MHz level, scaling pulse energies and intensities. With only 540 mW of absorbed pump power, 98 fs pulses with energies of 9.9 nJ and peak powers of ~101 kW, corresponding to 95 mW of average power at a repetition rate of 9.58 MHz, were generated. By increasing the intracavity negative dispersion, 310 fs pulses with energies of 15.2 nJ and peak powers of ~49 kW, corresponding to 160 mW of average power at 10.51 MHz repletion rate, were also generated. These results demonstrate that low-cost MPC Cr[superscript 3+]-doped colquiriite lasers can generate pulse energies and intensities comparable to more expensive Ti:sapphire lasers.