Period doubling of an 84-MHz repetition-rate Kerr-lens mode-locked Ti:sapphire laser operated at 830 nm and producing ~300mW of average power has been observed and explained in terms of total mode locking of TEM00 and TEM01 modes in an effective confocal cavity. This configuration leads to a spatial sweeping action of a single-peaked pulse at 42 MHz. Period tripling and quadrupling is observed for certain cavity configurations.
© 1998 Optical Society of America
Daniel Côté and Henry M. van Driel, "Period doubling of a femtosecond Ti:sapphire laser by total mode locking," Opt. Lett. 23, 715-717 (1998)