Design, fabrication and application of dispersive mirrors with a SiO2 sculptured layer

Abstract

We report on the design, fabrication and application of dispersive mirrors (DMs) with a SiO2 sculptured layer. The group delay dispersion (GDD) of the DMs are -200 fs2 in the spectral range from 680 to 920 nm. DMs with a multilayer structure consisting of a SiO2 sculptured layer with a low refractive index of ~1.09 fabricated by glancing-angle deposition (GLAD) on top of a conventional chirped film stack fabricated by dual-ion beam sputtering are designed and fabricated. The GDD oscillations of the DMs could be significantly reduced compared to the conventional chirped film stack without the SiO2 sculptured layer while maintaining a large GDD of several hundred femtoseconds squared and a wide dispersion bandwidth. For the first time, a single DM with a SiO2 sculptured layer has been successfully applied in a fiber chirped system without being used in DM-pair, which can realize the compression of laser pulses to 16fs.