Azimuthal distinguishability of entangled photons generated in spontaneous parametric down-conversion
Clara I. Osorio, Gabriel Molina‐Terriza, Blanca G. Font, Juan P. Torres · Optics Express · 2007
We experimentally demonstrate that paired photons generated in different sections of a down-conversion cone, when some of the interacting waves show Poynting vector walk-off, carry different spatial correlations, and therefore a different degree of spatial entanglement. This is shown to be in agreement with theoretical results. We also discuss how this azimuthal distinguishing information of the down-conversion cone is relevant for the implementation of quantum sources aimed at the generation of entanglement in other degrees of freedom, such as polarization.