Novel method to suppress noise in harmonically modelocked erbium fibre lasers

A novel method to suppress noise in a high harmonic mode-locked erbium fibre laser is proposed and realised for the first time, dithering the cavity length at a kilohertz rate. This method makes only one supermode in the laser dominant and suppresses the others. A fibre laser so stabilised has enabled 2.5 Gbit/s soliton transmission over 205 km fibre remaining error free for 100 min, and in a recirculating loop achieving a 10/sup -9/ bit error rate at 12000 km, respectively. >