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Research in Optical Sciences

High-purity atom resonant pairs of indistinguishable photons via filtered down-conversion

Joanna A. Zielińska, Federica A. Beduini, Morgan W. Mitchell

Published Jan 1, 2014• 0 citations
Publisher

Abstract

We present a novel method of generating narrowband atom-resonant photon pairs with a cavity-enhanced SPDC source. Using a Faraday Anomalous Dispersion Optical Filter, we select only a cavity mode containing identical pairs, which we demonstrate by measuring statistical properties of output photons.
DOI
10.1364/hilas.2014.jw2a.60

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Photonic quantum technologies require efficient sources of pure single photons. We present a heralded single-photon source based on spontaneous parametric down-conversion in a monolithic cavity optimized for high spectral and spatial purity. The source heralds single photons at a wavelength of 1540 nm and a spectral bandwidth of 168 MHz, with a maximum heralding efficiency of 70% including all transmission and detection losses, while keeping the multi-photon contamination below 3%. The cavity enhancement predominantly generates photons into the central cavity mode, with a theoretical upper bound on the spectral purity of 79.4% arising from nonzero overlap with adjacent cavity modes. Spectral isolation of the central cavity mode with an etalon yields an increased measured spectral purity of (96.2 ±\pm± 2.7)%.