title: Storage and retrieval of vector beams of light in a multiple-degree-of-freedom quantum memory.
abstract: The full structuration of light in the transverse plane, including intensity, phase and polarization, holds the promise of unprecedented capabilities for applications in classical optics as well as in quantum optics and information sciences. Harnessing special topologies can lead to enhanced focusing, data multiplexing or advanced sensing and metrology. Here we experimentally demonstrate the storage of such spatio-polarization-patterned beams into an optical memory. A set of vectorial vortex modes is generated via liquid crystal cell with topological charge in the optic axis distribution, and preservation of the phase and polarization singularities is demonstrated after retrieval, at the single-photon level. The realized multiple-degree-of-freedom memory can find applications in classical data processing but also in quantum network scenarios where structured states have been shown to provide promising attributes, such as rotational invariance.
authors.affiliation: Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University, Collège de France, 4 Place Jussieu, Paris 75005, France.
authors.forename: Valentina
authors.identifier: http://orcid.org/0000-0002-0779-1971
authors.initials: V
authors.lastname: Parigi
authors.affiliation: Dipartimento di Fisica, 'Sapienza' Università di Roma, Roma I-00185, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: D'Ambrosio
authors.affiliation: Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University, Collège de France, 4 Place Jussieu, Paris 75005, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Arnold
authors.affiliation: Dipartimento di Fisica, Università di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Napoli 80126, Italy.|CNR-SPIN, Complesso Universitario di Monte S. Angelo, Napoli 80126, Italy.
authors.forename: Lorenzo
authors.identifier: http://orcid.org/0000-0002-1154-8966
authors.initials: L
authors.lastname: Marrucci
authors.affiliation: Dipartimento di Fisica, 'Sapienza' Università di Roma, Roma I-00185, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Sciarrino
authors.affiliation: Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University, Collège de France, 4 Place Jussieu, Paris 75005, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Laurat