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Raman scattering effects on correlated photon-pair generation in chalcogenide

Alex S. Clark, Matthew J. Collins, Alexander C. Judge, Eric C. Magi, Chunle Xiong, Benjamin J. Eggleton

Published Jul 10, 2012• 34 citations

Abstract

In this paper we investigate uncorrelated noise from spontaneous Raman scattering (SpRS) and its effect on photon-pair generation in chalcogenide (As2S3). We measure a coincidence-to-accidental ratio (CAR) of 4.2 in a 7 cm As2S3 single-mode fiber, with enhancements from our previous result attributed to pulsed pumping and cooling. Using an analytical model we characterize the magnitude of the SpRS at different temperatures. Our analysis shows that even after cooling to liquid nitrogen temperature (77 K), SpRS is still significant. For large detunings from the pump, the dependence on temperature for the Stokes SpRS intensity becomes negligible, so cooling is not a complete solution to improve the quality of the photon source.

DOI: 10.1364/oe.20.016807

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