title: Classical analogue of displaced Fock states and quantum correlations in Glauber-Fock photonic lattices.
abstract: Coherent states and their generalizations, displaced Fock states, are of fundamental importance to quantum optics. Here we present a direct observation of a classical analogue for the emergence of these states from the eigenstates of the harmonic oscillator. To this end, the light propagation in a Glauber-Fock waveguide lattice serves as equivalent for the displacement of Fock states in phase space. Theoretical calculations and analogue classical experiments show that the square-root distribution of the coupling parameter in such lattices supports a new family of intriguing quantum correlations not encountered in uniform arrays. Because of the broken shift invariance of the lattice, these correlations strongly depend on the transverse position. Consequently, quantum random walks with this extra degree of freedom may be realized in Glauber-Fock lattices.
authors: Institute of Applied Physics, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany. robert.keil@uni-jena.de
authors: Robert
authors: R
authors: Keil
authors: Armando
authors: A
authors: Perez-Leija
authors: Felix
authors: F
authors: Dreisow
authors: Matthias
authors: M
authors: Heinrich
authors: Hector
authors: H
authors: Moya-Cessa
authors: Stefan
authors: S
authors: Nolte
authors: Demetrios N
authors: DN
authors: Christodoulides
authors: Alexander
authors: A
authors: Szameit