Sub-two-cycle pulses from a Kerr-lens mode-locked Ti:sapphire laser

Pulses shorter than two optical cycles with bandwidths in excess of 400??nm have been generated from a Kerr-lens mode-locked Ti:sapphire laser with a repetition rate of 90??MHz and an average power of 200??mW.?Low-dispersion prisms and double-chirped mirrors provide broadband controlled dispersion and high reflectivity. These pulse durations are to our knowledge the shortest ever generated directly from a laser oscillator.