Optics Express

Remote preparation of complex spatial states of single photons and verification by two-photon coincidence experiment

Yoonshik Kang, Kiyoung Cho, Jaewoo Noh, Dashiell L. P. Vitullo, Cody C. Leary, Michael G. Raymer

Published Jan 11, 2010• 13 citations

Abstract

We propose and provide experimental evidence in support of a theory for the remote preparation of a complex spatial state of a single photon. An entangled two-photon source was obtained by spontaneous parametric down-conversion, and a double slit was placed in the path of the signal photon as a scattering object. The signal photon was detected after proper spatial filtering so that the idler photon was prepared in the corresponding single-photon state. By using a two-photon coincidence measurement, we obtained the Radon transform, at several longitudinal distances, of the single-photon Wigner distribution function modified by the double slit. The experimental results are consistent with the idler photon being in a pure state. An inverse Radon transformation can, in principle, be applied to the measured data to reconstruct the modified single-photon Wigner function, which is a complete representation of the amplitude and phase structure of the scattering object.

DOI: 10.1364/oe.18.001217

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