title: Optics in curved space.
abstract: We experimentally study the impact of intrinsic and extrinsic curvature of space on the evolution of light. We show that the topology of a surface matters for radii of curvature comparable with the wavelength, whereas for macroscopically curved surfaces only intrinsic curvature is relevant. On a surface with constant positive Gaussian curvature we observe periodic refocusing, self-imaging, and diffractionless propagation. In contrast, light spreads exponentially on surfaces with constant negative Gaussian curvature. For the first time we realized two beam interference in negatively curved space.
authors.affiliation: Max Planck Institute for the Science of Light, 91058 Erlangen, Germany.
authors.forename: Vincent H
authors.initials: VH
authors.lastname: Schultheiss
authors.forename: Sascha
authors.initials: S
authors.lastname: Batz
authors.forename: Alexander
authors.initials: A
authors.lastname: Szameit
authors.forename: Felix
authors.initials: F
authors.lastname: Dreisow
authors.forename: Stefan
authors.initials: S
authors.lastname: Nolte
authors.forename: Andreas
authors.initials: A
authors.lastname: Tünnermann
authors.forename: Stefano
authors.initials: S
authors.lastname: Longhi
authors.forename: Ulf
authors.initials: U
authors.lastname: Peschel