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arXiv · 1404.6914

Crossed crystal scheme for fs-pulsed entangled photon generation in ppKTP

Thomas Scheidl·Felix Tiefenbacher·Robert Prevedel·Fabian Steinlechner·Rupert Ursin·Anton Zeilinger
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Abstract

We demonstrate a novel scheme for femto-second pulsed spontaneous parametric down-conversion in periodically poled KTP crystals. Our scheme is based on a crossed crystal configuration with collinear quasi-phase-matching. The non-degenerate photon pairs are split in a fiber-based wavelength division multiplexer. The source is easier to align than common pulsed sources based on bulk BBO crystals and exhibits high-quality polarization entanglement as well as non-classical interference capabilities. Hence, we expect this source to be a well-suited candidate for multi-photon state generation e.g. for linear optical quantum computation and quantum communication networks.

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Thomas Scheidl, Felix Tiefenbacher, Robert Prevedel, Fabian Steinlechner, Rupert Ursin, Anton Zeilinger. 2014-04-28. Crossed crystal scheme for fs-pulsed entangled photon generation in ppKTP. https://doi.org/10.1103/physreva.89.042324

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