Broad-band and ultrasensitive pulse characterization using frequency-resolved optical gating via four-wave mixing in a semiconductor optical amplifier

We present a frequency-resolved optical gating geometry permitting the characterization of 1-mW average power 2.5-ps pulses over the whole C-band at 10-GHz repetition rate. This represents an order of magnitude improvement in sensitivity over other reported self-referenced characterization techniques. Measurements of pulses from an actively mode-locked fiber laser are reported.