title: Distribution of squeezed states through an atmospheric channel.
abstract: Continuous variable quantum states of light are used in quantum information protocols and quantum metrology and known to degrade with loss and added noise. We were able to show the distribution of bright polarization squeezed quantum states of light through an urban free-space channel of 1.6 km length. To measure the squeezed states in this extreme environment, we utilize polarization encoding and a postselection protocol that is taking into account classical side information stemming from the distribution of transmission values. The successful distribution of continuous variable squeezed states is accentuated by a quantum state tomography, allowing for determining the purity of the state.
authors.affiliation: Max Planck Institute for the Science of Light, Günther-Scharowsky-Straße 1/Building 24, 91058 Erlangen, Germany and Institute of Optics, Information and Photonics, University of Erlangen-Nuremberg (FAU), Staudtstraße 7/B2, 91058 Erlangen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Peuntinger
authors.affiliation: Max Planck Institute for the Science of Light, Günther-Scharowsky-Straße 1/Building 24, 91058 Erlangen, Germany and Institute of Optics, Information and Photonics, University of Erlangen-Nuremberg (FAU), Staudtstraße 7/B2, 91058 Erlangen, Germany and Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU, Paul-Gordan-Straße 6, 91052 Erlangen, Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Heim
authors.affiliation: Max Planck Institute for the Science of Light, Günther-Scharowsky-Straße 1/Building 24, 91058 Erlangen, Germany and Institute of Optics, Information and Photonics, University of Erlangen-Nuremberg (FAU), Staudtstraße 7/B2, 91058 Erlangen, Germany.
authors.forename: Christian R
authors.initials: CR
authors.lastname: Müller
authors.affiliation: Max Planck Institute for the Science of Light, Günther-Scharowsky-Straße 1/Building 24, 91058 Erlangen, Germany and Institute of Optics, Information and Photonics, University of Erlangen-Nuremberg (FAU), Staudtstraße 7/B2, 91058 Erlangen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Gabriel
authors.affiliation: Max Planck Institute for the Science of Light, Günther-Scharowsky-Straße 1/Building 24, 91058 Erlangen, Germany and Institute of Optics, Information and Photonics, University of Erlangen-Nuremberg (FAU), Staudtstraße 7/B2, 91058 Erlangen, Germany and Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU, Paul-Gordan-Straße 6, 91052 Erlangen, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Marquardt
authors.affiliation: Max Planck Institute for the Science of Light, Günther-Scharowsky-Straße 1/Building 24, 91058 Erlangen, Germany and Institute of Optics, Information and Photonics, University of Erlangen-Nuremberg (FAU), Staudtstraße 7/B2, 91058 Erlangen, Germany and Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU, Paul-Gordan-Straße 6, 91052 Erlangen, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Leuchs