title: Higher-order Laguerre-Gauss mode generation and interferometry for gravitational wave detectors.
abstract: We report on the first experimental demonstration of higher-order Laguerre-Gauss (LG(p)(ℓ)) mode generation and interferometry using a method scalable to the requirements of gravitational wave (GW) detection. GW detectors which use higher-order LG(p)(ℓ) modes will be less susceptible to mirror thermal noise, which is expected to limit the sensitivity of all currently planned terrestrial detectors. We used a diffractive optic and a mode-cleaner cavity to convert a fundamental LG(0)(0) Gaussian beam into an LG(3)(3) mode with a purity of 98%. The ratio between the power of the LG(0)(0) mode of our laser and the power of the LG(3)(3) transmitted by the cavity was 36%. By measuring the transmission of our setup using the LG(0)(0), we inferred that the conversion efficiency specific to the LG(3)(3) mode was 49%. We illuminated a Michelson interferometer with the LG(3)(3) beam and achieved a visibility of 97%.
authors.affiliation: Laboratoire Astroparticule et Cosmologie, Université Paris Diderot, CNRS, IN2P3-CEA, DSM/IRFU-Observatoire de Paris, 10 rue Alice Domon et Léonie Duquet, 75013 Paris, France. granata@apc.univ-paris7.fr
authors.forename: M
authors.initials: M
authors.lastname: Granata
authors.forename: C
authors.initials: C
authors.lastname: Buy
authors.forename: R
authors.initials: R
authors.lastname: Ward
authors.forename: M
authors.initials: M
authors.lastname: Barsuglia