Quantum nanolaminates: revolution in dielectric layer designs

As part of the "QuantUV" research project, the R&D department in Olching investigated how the absorption edge of anti-reflective coatings can be shifted into the short wavelength range by using quantum nanolaminates (QNL).  Head of R&D Dr. Sina Malobabic will be presenting the results to an international audience of experts at two SPIE events in Strasbourg on April 8 and 9.

Absorption goes hand in hand with the optical band gap energy.  QNLs can be used to produce metamaterials that offer new possibilities for improving the absorption of optical layer designs in the UV range.  The tunnel effect known from quantum physics is used to influence the refractive index and the band gap energy independently of each other.  These material constants are usually in a fixed correlation to each other.  The aim of LASER COMPONENTS' research was to shift the absorption edge in the UV wavelength range to shorter wavelengths for anti-reflective coatings.  The team used nanolaminates made of hafnium dioxide (HfO2 - low band gap energy) and silicon dioxide (SiO2 - high band gap energy) for this purpose.

"Until now, it was only possible to marginally improve the absorption of laser optics in the UV range by annealing," says Dr. Malobabic.  "Based on our current state of research, we are confident that we will soon be able to use QNL in order to extend the transmission range at these wavelengths."