Broad-spectrum frequency comb generation and carrier-envelope offset frequency measurement using the second harmonic generation of a mode-locked fiber laser

Frequency comb spanning more than one octave has been achieved by injecting the second harmonic generation (780 nm) of a mode-locked fiber laser (1.56 /spl mu/m) into a photonic crystal fiber. We propose and realize a novel interferometric scheme for observing the carrier-envelope offset frequency.