Design, fabrication and characterization of dispersive mirrors for ultrafast lasers

The design, fabrication and characterization of the dispersive multilayers are presented in this paper. Two kinds of dispersive mirror (High dispersion and 700-900nm Gires-Tournois mirrors) are designed by employing Particle Swarm Optimization method which demonstrates fast convergence speed and less dependence on the initial parameters. The mirrors are experimentally fabricated by home-made dual ion beam sputtering system with stable deposition rate and high density. A white light interferometry is built for precisely measuring the dispersion properties. A novel wavelet-based differentiation approach is introduced with considerable resistance to measurement error. The good agreement between the measured and designed results verifies the accuracy of both the fabrication and characterization method. Finally, two applications of Yb-doped photonic crystal fiber laser and Ti:Sapphire crystal oscillation cavity, which use our fabricated mirrors for dispersion compensation, are presented. Good output characteristics of both the two ultrafast laser systems are obtained.