Attosecond experiments require incredibly well-synchronized laser pulses. Because coherent EUV/soft x-ray sources are limited in their tunability, this must be addressed by pulse-shaping attosecond optics such as laser mirrors. Therfore Attosecond optics for extreme ultraviolet lasers should be designed for maximum control of the central wavelength/energy, spectral shape, spectral phase, and pulse duration.
How this is achieved and what the current state of mirror technology is today is explained by Olivia Wheeler and Alexander Guggenmos in an article now published in LaserFocus World magazine.
The full article can be viewed here: