Chirped pulse Raman amplification with compression in air-core photonic bandgap fiber

An all-fiber chirped pulse amplification scheme based on Raman amplifiers and compression in air-core photonic bandgap fiber is demonstrated for the first time. Pulse chirping was achieved through nonlinear propagation in the amplifiers and a net compression factor of 53 was achieved. Output pulses presented sub-picosecond durations. Output peak powers approached 1 kW, being 3 orders of magnitude higher than those obtainable with Raman amplifiers without the chirped pulse amplification setup. The demonstrated scheme may instigate the use of fiber Raman amplifiers outside optical communications, as it is simple, robust, and may be built to operate at virtually any optical wavelength.