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Conference on Lasers and Electro-Optics

Quantum Frequency Down-Conversion of Single Photons from a Quantum Dot to the Telecom Band

Andreas Lenhard, Sebastian Zaske, Christian Kessler, Jan Kettler, Carsten Arend, Christian Hepp, Roland Albrecht, W.-M. Schulz, Michael Jetter, Peter Michler, Christoph Becher

Published Jan 1, 2012• 0 citations
Publisher

Abstract

We report the frequency downconversion of single photons from a quantum dot (710nm) to the telecommunications O-band with over-all conversion efficiency of 33%. We show the conservation of nonclassical statistics and coherence properties during conversion.
DOI
10.1364/qels.2012.qth5b.6

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Near-infrared single photon sources in telecommunication bands, especially at 1550 nm, are required for long-distance quantum communication. Here a down-conversion quantum interface is implemented, where the single photons emitted from single InAs quantum dot at 864 nm is down converted to 1552 nm by using a fiber-coupled periodically poled lithium niobate (PPLN) waveguide and a 1.95 μmm pump laser, and the frequency conversion efficiency is ∼40%. The single-photon purity of quantum dot emission is preserved during the down-conversion process, i.e., g (2) (0), only 0.22 at 1552 nm. This present technique advances the III–V semiconductor quantum dots as a promising platform for long-distance quantum communication.