title: Precision angle sensor using an optical lever inside a Sagnac interferometer.
abstract: We built an ultra-low-noise angle sensor by combining a folded optical lever and a Sagnac interferometer. The instrument has a measured noise floor of 1.3 prad/√Hz at 2.4 kHz. We achieve this record angle sensitivity using a proof-of-concept apparatus with a conservative N=11 bounces in the optical lever. This technique could be extended to reach subpicoradian/√Hz sensitivities with an optimized design.
authors.affiliation: Department of Physics, Stanford University, Stanford, California 94305, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Hogan
authors.forename: J
authors.initials: J
authors.lastname: Hammer
authors.forename: S-W
authors.initials: SW
authors.lastname: Chiow
authors.forename: S
authors.initials: S
authors.lastname: Dickerson
authors.forename: D M S
authors.initials: DM
authors.lastname: Johnson
authors.forename: T
authors.initials: T
authors.lastname: Kovachy
authors.forename: A
authors.initials: A
authors.lastname: Sugarbaker
authors.forename: M A
authors.initials: MA
authors.lastname: Kasevich