Optical parametric chirped pulse amplification based on photonic crystal fibre

A compact two-stage optical parametric chirped pulse amplifier based on photonic crystal fibre is demonstrated. A 1064-nm soliton pulse is obtained in a home-made photonic crystal fibre (PCF) with femtosecond pulse pumping and then amplified to 2 mJ in an Nd:YAG regenerative amplifier. After the amplified pulses pass through the LBO crystal, the 532-nm double-frequency light with an energy of 0.8 mJ and a duration of over 100 ps at 10-Hz repetition rate is generated as a pump source in the following two-stage optical parametric amplification (OPA). The 850-nm chirped signal light gain from the stretcher is 1.5 × 10⁴ in the first-stage OPA while it is 120 in the second-stage OPA. The total signal gain of optical parametric chirped pulse amplification (OPCPA) can reach 1.8 × 10⁶.