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DOE OSTI · 21541394

Type-I spontaneous parametric down-conversion with a strongly focused pump

Di Lorenzo Pires, H·Exter, M P. van
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Abstract

We experimentally study the spatial properties of the field generated by spontaneous parametric down-conversion (SPDC) when the pump laser beam is strongly focused in the nonlinear crystal. Special attention is paid to classical intensity measurements with a CCD camera. We introduce the concept of a classical equivalent source that replicates all the coherence properties of SPDC light and explains all our experimental results. We show that, in contrast with experiments with a well-collimated pump, here both the phase-matching conditions and the position of the focusing plane determine the measured intensity profiles in the image plane of the crystal. The transition from the near-field regime to the far field is investigated. Measurements of two-photon correlations under strong focusing are also presented and the special features thereof are discussed.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYBEAMSBOSONSCHARGE-COUPLED DEVICESCONVERSIONCORRELATIONSCRYSTALSELECTROMAGNETIC RADIATIONELEMENTARY PARTICLESFOCUSINGLASER RADIATIONMANY-BODY PROBLEMMASSLESS PARTICLESNONLINEAR PROBLEMSOPTICAL PUMPINGPHOTON BEAMSPHOTONSPUMPINGRADIATIONSSEMICONDUCTOR DEVICESTWO-BODY PROBLEMVISIBLE RADIATION

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Di Lorenzo Pires, H, Exter, M P. van. 2011-03-15. Type-I spontaneous parametric down-conversion with a strongly focused pump. https://doi.org/10.1103/physreva.83.033837

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