title: Sub-shot-noise heterodyne polarimetry.
abstract: We report an experimental demonstration of a heterodyne polarization rotation measurement with a noise floor 4.8 dB below the optical shot noise by use of classically phase-locked quantum twin beams emitted above threshold by an ultrastable type II Na:KTP cw optical parametric oscillator. We believe that this is the largest noise reduction achieved to date in optical phase-difference measurements.
authors.affiliation: Department of Physics, University of Virginia, 382 McCormick Road, Charlottesville, Virginia 22904-4714, USA.
authors.forename: Sheng
authors.initials: S
authors.lastname: Feng
authors.forename: Olivier
authors.initials: O
authors.lastname: Pfister