We describe efficient, compact femtosecond Cr:LiSAF lasers with a reduced component count that combine greater simplicity with improved performance. We observe transform-limited pulses as short as 136 fs centered on 859 nm at a 470 MHz repetition rate. 20 mW of average output power has been achieved for less than 100 mW of incident diode-laser pump power - an optical-to-optical conversion efficiency of over 20%. We have demonstrated an entirely portable, self-contained, battery-powered version of this laser on a 22x28cm2 breadboard, with an electrical-to-optical efficiency of almost 4%. Using four pump laser diodes, we have also achieved operational regimes providing either gigahertz repetition rates or kilowatt peak powers.
- optical conversion