Experimental demonstration on 400 nm-scale bandwidth optical parametric chirped-pulse amplification based on mixed cascaded crystals

We present an optical parametric chirped -pulse amplification (OPCPA) based on mixed cascaded crystals, taking advantage of the unique parametric phase -matching of lithium triborate (LiB3O5 , LBO) and yttrium calcium oxyborate ((YCa4O(BO3)3 , YCOB) crystals. The OPCPA properties of LBO at 880 nm and YCOB at 750 nm are studied respectively. After amplification by two LBO and two YCOB crystals, a total signal gain of 108 and spectral bandwidth close to 400 nm is obtained. After accurate dispersion compensation with a gratingpair compressor and chirped mirror compensator, a pulse duration of 9.4 fs is obtained by a SHG-frequency-resolved optical grating (FROG). This approach will be of great significance in high energy amplifier for high peak power few -cycle laser sources. (c) 2024 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement