Simplified cavity designs for efficient and compact femtosecond Cr:LiSAF lasers

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 diodelaser 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 22 x 28 cm(2) 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. (C) 2002 Elsevier Science B.V. All rights reserved.