Optical and mechanical properties of ion-beam-sputtered MgF$_2$ thin films for gravitational-wave interferometers

M. Granata (1, 2) , A. Amato (3) , M. Bischi (4, 5) , M. Bazzan (6) , G. Cagnoli (3) , M. Canepa (7, 8) , M. Chicoine (9) , A. Di Michele (10) , G. Favaro (6) , D. Forest (1, 2) , G.M. Guidi (4, 5) , G. Maggioni (6) , F. Martelli (4, 5) , M. Menotta (4) , M. Montani (4, 5) , F. Piergiovanni (4, 5) , F. Schiettekatte (9)

1 LMA - Laboratoire des matériaux avancés
2 IP2I Lyon - Institut de Physique des 2 Infinis de Lyon
3 iLM - SOPRANO - iLM - Spectroscopies optiques des matériaux verres, amorphes et à nanoparticules
4 Università degli Studi di Urbino 'Carlo Bo'
5 INFN, Sezione di Firenze - Istituto Nazionale di Fisica Nucleare, Sezione di Firenze
6 Unipd - Università degli Studi di Padova = University of Padua
7 UniGe - Università degli studi di Genova = University of Genoa
8 INFN, Sezione di Genova - Istituto Nazionale di Fisica Nucleare, Sezione di Genova
9 UdeM - Université de Montréal
10 UNIPG - Università degli Studi di Perugia = University of Perugia

Brownian thermal noise associated with highly reflective coatings is a fundamental limit for several precision experiments, including gravitational-wave detectors. Research is currently ongoing to find coatings with low thermal noise that also fulfill strict optical requirements such as low absorption and scatter. We report on the optical and mechanical properties of ion-beam-sputtered magnesium fluoride thin films and we discuss the application of such coatings in current and future gravitational-wave detectors.

Domaines: Instrumentations et Détecteurs [physics.ins-det]

M. Granata, A. Amato, M. Bischi, M. Bazzan, G. Cagnoli, et al.. Optical and mechanical properties of ion-beam-sputtered MgF$_2$ thin films for gravitational-wave interferometers. Phys.Rev.Applied, 2022, 17 (3), pp.034058. ⟨10.1103/PhysRevApplied.17.034058⟩. ⟨hal-03436777⟩