Using an ion-implanted semiconductor saturable absorber mirror researchers at Australian National University in Canberra and Macquarie University in Sydney, Australia, have achieved passive mode-locking in a diode-pumped, self-frequency-doubling Yb:YAB laser.As reported in the March 15 issue of Optics Letters, the locking resulted in transform-limited IR pulses with widths of 198 fs to 1.4 ps and average powers ranging from 440 to 660 mW when the frequency doubling was far from phase matched. At 1040 nm, the pulses were produced with an optical efficiency of 24 percent.The researchers see these results as an indication that Yb:YAB lasers have potential for applications requiring high-power femtosecond generation, such as some micromachining processes.