Quantum correlations in position, momentum, and intermediate bases for a full optical field of view

摘要

We report an eight-element, linear-array, single-photon detector that uses multiple fibers of differing lengthsncoupled to a single detector, the timing information from which reveals the position in which the photonnwas measured. Using two such arrays and two detectors we measure the correlations of photons produced bynparametric downconversion, without recourse to mechanical scanning. Spatial light modulators acting as variablenfocal length lenses positioned between the downconversion crystal and the arrays allow us to switch betweennmeasurement of position, transverse momentum, or intermediate bases. We observe the product of the variancesnof the conditional probabilities for position and momentum to be more than an order of magnitude below thenclassical limit, realizing a full-field demonstration of the Einstein-Podolsky-Rosen paradox. Such, multistatenmeasurement technologies allow access to the higher information content of the photon based upon spatialnmodes.