Nonlinear Compression of Ultrashort-Pulse Laser to 36 fs With 556-MW Peak Power

The setup of nonlinear pulse compression with hollow-core photonic crystal fiber (HC-PCF) is demonstrated. In our experiment, the HC-PCF is just put in the air with no extra gas fill. The spectrum is effectively broadened to more than 60 nm by delivering the ultrashort laser in the HC-PCF and compressing the pulse with Gires–Tournois interferometer-type dispersion mirrors. The initial pulse duration of 279 fs has been shortened to 36 fs with $20\mu \text{J}$ of pulse energy, which corresponds to a peak power of about 556 MW. To our best knowledge, it is the highest peak power obtained from the solid-state laser at the wavelength around $1~\mu \text{m}$ by using Kagome-type HC-PCF without extra gas fill. With precise dispersion compensation and higher input pulse energy, even shorter pulse width and higher peak power can be obtained.