Materials for Advanced Detectors 2025

Session

MAD25: Session 3. Coatings

7 Oct 2025, 12:50

Max-Born-Saal

Description

MAD: Coatings

61. Introduction on Coating Research

alex amato (Maastricht University - Nikhef)

07/10/2025, 12:50

37. Development of mixed oxide coatings for future detectors

Mariana Fazio

07/10/2025, 13:00

Talk

Future gravitational-wave observatories will require larger area mirror coatings with reduced thermal noise, absorption loss and scattering loss. The development of germanium dioxide mixed with titanium dioxide (TiO$_2$:GeO$_2$) for A+ LIGO has highlighted the need for additional R&D to address specific challenges of mixed oxide coatings.

We will present an overview of the development of...

41. Evolution Optical Coating Thin Films Following Thermal Annealing: IR Spectroscopic Ellipsometry and Raman Investigation

Shima Samandari (OptMatLab, Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, 16146 Genova, Italy)

07/10/2025, 13:15

Talk

The development of future gravitational wave observatories such as the Einstein Telescope requires the development of multilayer mirror coatings with low absorption and constant refractive indices [1]. These coatings, which are usually amorphous mixed oxides, are deposited by ion beam sputtering. Thermal annealing after deposition is used to enhance the performance of the coatings....

51. Development of Silicon Nitride by RF Magnetron Sputtering for GW Coatings

Dr Simone Marchetti (University of Padova - Department of Physics and Astronomy, Istituto Nazionale di Fisica Nucleare - Sezione di Padova), Simone Marchetti

07/10/2025, 13:30

Talk

Gravitational wave (GW) interferometers necessitate the use of specialized mirrors designed to minimize mechanical loss and absorption, thereby ensuring the required sensitivity for effective gravitational wave detection.
Currently, a stack of alternating layers of tantalum oxide (Ta$_2$O$_5$) combined with titanium oxide (TiO$_2$) and silicon oxide (SiO$_2$) is considered the state of the...

36. Advancing Gravitational-Wave Detection Through Ion Implantation for Low Thermal Noise Coatings

Luca Massaro

07/10/2025, 13:45

Talk

Coating thermal noise limits the sensitivity of gravitational-wave detectors in the most sensitive frequency band. As third-generation detectors, like the Einstein Telescope or LIGO Voyager, advance toward cryogenic interferometers to reduce thermal noise, current coating materials such as Ta$_{2}$O$_{5}$ and SiO$_{2}$ become inadequate due to their high mechanical loss at low temperatures....

35. Optical Simulations of Ion Implanted Layers for Advanced Gravitational-Wave Detection

Dr Ismail El Ouedghiri-Idrissi (Maastricht University)

07/10/2025, 14:00

Talk

Thermal noise originating from mirror coatings remains a key limitation to the sensitivity of gravitational-wave detectors, particularly within their most sensitive frequency range. As next-generation detectors, such as the Einstein Telescope and LIGO Voyager, move toward cryogenic temperatures to mitigate this noise source, conventional coating materials like...

52. Measuring the mechanical and optical losses of coatings in cryogenic conditions using an optomechanical cavity

Nicole Busdon

07/10/2025, 14:45

Talk

One of the most critical components of gravitational wave interferometers are their mirror test masses which are coated with multilayer dielectric films to achieve the required reflectivity. However, these coatings introduce coating thermal noise (CTN) that limits the sensitivity of the detectors, particularly in the crucial frequency band from 20 to 2000 Hz. To reduce CTN, one of the two...

47. Vacuum issues and possible mitigations in cryogenic gravitational wave detectors and cold mirrors test benches

Roberto Cimino

07/10/2025, 15:00

Talk

In the upcoming third generation of gravitational wave (GW) detectors, the push toward low-frequency detection necessitates the use of cryogenic optics at temperatures as low as a few Kelvin. This unprecedented technological challenge has spurred a series of R&D efforts aimed at validating the use of cryogenic optics in GW detectors. The performance of cryo-mirrors must be carefully measured...