Chirped Mirrors & Dispersive Coatings for Ultrafast Lasers

As part of our recently enlarged program for ultrafast laser applications, LASEROPTIK offers chirped mirrors, matched pairs and dispersive coatings. In addition, the use of high quality substrates with superior roughness from our Premium (<2Ȧ rms) or super-polished (<1Ȧ rms) product line helps to achieve lowest losses for these critical components. A variety of standard sizes is available from stock.

For example, chirped mirrors compensate for the dispersion introduced by other elements like the laser crystal in a laser cavity. Or they serve as compressors in chirped pulse amplification systems (CPA). They include types like

• mirrors with low or optimized GDD,
• GTI mirrors, i.e. highly dispersive narrow bandwidth mirrors,
• chirped mirrors and matched mirror pairs,
• octave-spanning broadband chirped mirrors with moderate GDD,
• partial reflectors,
• coatings used within an OPO.

In general, various spectral requirements can be combined with a GDD value as target for coating design and production, e.g. for OPO optics or partial reflectors. The dispersion management is highly depending on the coating design and a sub-nanometer manufacturing accuracy for GDD optimized optics. At LASEROPTIK, this precision is ensured by the sophisticated method of Ion Beam Sputtering (IBS).

With the help of an optical in-situ process control based on the calculated design, the deposition of complex, custom tailored stacks of many (n > 70) non­quarterwave layers is performed. The results are verified ex-situ by in-house GDD measurements.