Design, production, and characterization of a pair of positive and negative high dispersive mirrors for chirped pulse amplification systems.

ABSTRACT

We report a novel modified Gires-Tournois interferometer (MGTI) starting design for high-dispersive mirrors (HDMs). The MGTI structure combines multi-G-T and conjugate cavities and introduces a large amount of dispersion while covering a wide bandwidth. With this MGTI starting design, a pair of positive (PHDM) and negative highly dispersive mirrors (NHDM) providing group delay dispersions of +1000 fs2 and -1000 fs2 in the spectral range of 750 nm to 850 nm is developed. The pulse stretching and compression capabilities of both HDMs are studied theoretically by simulating the pulse envelopes reflected from the HDMs. A near Fourier Transform Limited pulse is obtained after 50 bounces on each positive and negative HDM, which verifies the excellent matching between the PHDM and NHDM. Moreover, the laser-induced damage properties of the HDMs are studied using laser pulses of 800 nm and 40 fs. The damage thresholds of the PHDM and NHDM are approximately 0.22 J/cm2 and 0.11 J/cm2, respectively. The laser-induced blister structure of the HDMs is observed, the formation and evolution processes of the blister are evaluated.