Double-Pass Multiple-Plate Continuum for High-Temporal-Contrast Nonlinear Pulse Compression

We propose a new architecture, double-pass multiple-plate continuum (DPMPC), for nonlinear pulse compression. In addition to having a smaller footprint, a double-pass configuration is designed to achieve substantial bandwidth broadening without incurring noticeable higher-order dispersion, thus improving the temporal contrast over those of the traditional single-pass geometry when only the quadratic spectral phase can be compensated. In our proof-of-concept experiment, 187 μJ, 190-fs Yb-based laser pulse is compressed to 20 fs with high throughput (75%), high Strehl ratio (0.76), and excellent beam homogeneity by using DPMPC. The subsequently generated octave-spanning spectrum exhibits a significantly raised blue tail compared with that driven by pulses from a single-pass counterpart.