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arXiv · 1108.0803

Classical analogue of displaced Fock states and quantum correlations in Glauber-Fock photonic lattices

Robert Keil·Armando Perez-Leija·Felix Dreisow·Matthias Heinrich·Hector Moya-Cessa·Stefan Nolte·Demetrios N. Christodoulides·Alexander Szameit
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Abstract

Coherent states and their generalisations, 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. Due to 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 realised in Glauber-Fock lattices.

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Robert Keil, Armando Perez-Leija, Felix Dreisow, Matthias Heinrich, Hector Moya-Cessa, Stefan Nolte, Demetrios N. Christodoulides, Alexander Szameit. 2011-08-03. Classical analogue of displaced Fock states and quantum correlations in Glauber-Fock photonic lattices. https://doi.org/10.1103/physrevlett.107.103601

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