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European Conference on Optical Communication

Squeezing and Photon-Statistics Measurements of 1550-nm Light Generated by Down-Conversion in Periodically Poled Lithium Niobate

Keiichi Hirano, Y. Takahashi, Naoto Namekata, S. Machida, Jonas Söderholm, Shuichiro Inoue, Sunao Kurimura

Published Sep 1, 2006• 0 citations
Publisher

Abstract

3 dB of measured squeezing is reported for pulsed 1550-nm light generated by down-conversion in bulk PPLN. Using different pump focuses, single- and coincidence-counts in agreement with both thermal and Poissonian photon-pair distributions were obtained.
DOI
10.1109/ecoc.2006.4801396

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The process of spontaneous parametric down-conversion (SPDC) in nonlinear crystals makes it fairly easy to generate entangled photon states. It has been known for some time that the conversion efficiency can be improved by employing quasi-phase-matching in periodically poled crystals. Using two single-photon detectors, we have analyzed the photon pairs generated by SPDC in a periodically poled lithium niobate crystal pumped by a femtosecond laser. Several parameters could be varied in our setup, allowing us to obtain data in close agreement with both thermal and Poissonian photon-pair distributions.