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arXiv · 1111.0829

Conclusive quantum steering with superconducting transition edge sensors

Devin H. Smith·Geoff Gillett·Marcelo de Almeida·Cyril Branciard·Alessandro Fedrizzi·Till J. Weinhold·Adriana Lita·Brice Calkins·Thomas Gerrits·Howard M. Wiseman·Sae Woo Nam·Andrew G. White
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Abstract

Quantum steering allows two parties to verify shared entanglement even if one measurement device is untrusted. A conclusive demonstration of steering through the violation of a steering inequality is of considerable fundamental interest and opens up applications in quantum communication. To date all experimental tests with single photon states have relied on post-selection, allowing untrusted devices to cheat by hiding unfavourable events in losses. Here we close this "detection loophole" by combining a highly efficient source of entangled photon pairs with superconducting transition edge sensors. We achieve an unprecedented ~62% conditional detection efficiency of entangled photons and violate a steering inequality with the minimal number of measurement settings by 48 standard deviations. Our results provide a clear path to practical applications of steering and to a photonic loophole-free Bell test.

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Devin H. Smith, Geoff Gillett, Marcelo de Almeida, Cyril Branciard, Alessandro Fedrizzi, Till J. Weinhold, Adriana Lita, Brice Calkins, Thomas Gerrits, Howard M. Wiseman, Sae Woo Nam, Andrew G. White. 2011-11-03. Conclusive quantum steering with superconducting transition edge sensors. https://doi.org/10.1038/ncomms1628

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