All-fibre diode pumped, femtosecond chirped pulseamplificationsystem

Abstract
A totally integrated all-fibre femtosecond chirped pulse amplification scheme is described. Transform-limited 670 fs pulses at a 3.1 MHz repetition rate, derived from a diode pumped Yb-Er figure-of-eight fibre laser, were temporally stretched, amplified in a diode pumped Yb-Er fibre amplifier and recompressed to give 900 fs pulses of 1.6 nJ energy and an average power of 4.8 mW. Chirped Bragg fibre gratings were used to stretch and recompress the pulses, in a novel configuration which minimises loss.