Abstract

We report on two newly developed types of dispersive mirrors. First type covers range of 1027–1033 nm, has 99.9% reflectance and −4500 fs² of group delay dispersion (GDD). When implementing these mirrors in Yb:YAG disk oscillator we observe changes on the surface of the mirrors due to thermal effects. Second type is high dispersive mirror (HDM) which provides GDD of −3000 fs² and covers wavelength range of 1020–1035 nm. The fabricated mirrors have reflectance 99.97%. We haven’t observed any thermal effects on the second type of HDM, it behaves similar to non-dispersive quarter wave stack mirrors. This HDM were successfully implemented in an Yb:YAG disk oscillator over 1 kW of intracavity circulated power. The reported mirrors expand possibilities of multilayer optics. The mentioned large GDD allows to compress the nanosecond pulses down to femtosecond range.

© 2011 AOS