GEMME G.

Amorphous films of tantalum oxide (Ta2O5) are widely applied to build highly reflective mirrors used in interferometric gravitational wave detectors, such as the Laser Interferometer Gravitational Wave Observatory. Despite a large number of studies, the structural properties of amorphous Ta2O5 on the local scale still deserve several further...

We determine the optical properties of amorphous, mixed titania-tantala coatings as a function of the mixing ratio and thermal annealing. The Urbach energy is proposed as a good estimator of the quality of the coatings.

The performance of optical cavities in gravitational wave detectors (GWD) is negatively affected by the growth of ice layers when operating at cryo temperatures. Loss of performance begins when the ice overlayer is only a few-nm thick. Careful planning is then required to minimize, monitor and take into account the presence of ultrathin ice on...