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Spatial and Spectral Mode Selection of Heralded Single Photons From Pulsed Parametric Down Conversion



Stefania Castelletto, Ivo P. Degiovanni, V Schettini, Alan L. Migdall


We describe an experiment in which photon pairs from a pulsed parametric down-conversion source were coupled into single-mode fibers with heralding efficiencies as high as 70%. Heralding efficiency or mode preparation efficiency is defined as the probability of finding a photon in a fiber in a definite state, given the detection of its twin. Heralding efficiencies were obtained for a range of down-conversion beam size configurations. Analysis of spatial and spectral mode selection, and their mutual correlation, guides one toward a practical procedure for engineering PDC single photons in a definite mode and spectral emission. The heralded photons were analyzed spectrally, for each beam configuration, to determine the interplay between transverse momentum and spectral entanglement on the preparation efficiency.
Optics Express
13 No 18


coupling efficiency, downconversion, fiber coupling, mode matching PDC, single mode, single-photon source


Castelletto, S. , Degiovanni, I. , Schettini, V. and Migdall, A. (2005), Spatial and Spectral Mode Selection of Heralded Single Photons From Pulsed Parametric Down Conversion, Optics Express, [online], (Accessed July 17, 2024)


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Created August 31, 2005, Updated October 12, 2021