Orateur
Description
In this talk, we present the loss characterization of the spare OMC at LAPP. We measured the OMC's internal losses and found them to be approximately 3.4% ± 0.1%, significantly higher than the expected value of around 1.4% ± 0.4%.
To investigate the origin of these excess losses, we examined two possible scattering-related contributions. The first is surface scattering, which generates a counter-propagating beam inside the cavity and can lead to backscattering towards the interferometer, as well as additional losses of the resonant TEM00 mode. We characterize this backscattered light and evaluate its contribution to the OMC losses. The second contribution is Rayleigh scattering in the fused silica substrate.
These measurements provide insight into the origin of the excess losses observed in the OMC.