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arXiv:0804.0716 · Physical Review Letters

Bell-Inequality Violation with a Triggered Photon-Pair Source

Robert James Young, R. M. Stevenson, A. J. Hudson, Christine A. Nicoll, D. A. Ritchie, Andrew J. Shields

Published Jan 23, 2009• 73 citations
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Abstract

Here we demonstrate, for the first time, violation of Bell's inequality using a triggered quantum dot photon-pair source without post-selection. Furthermore, the fidelity to the expected Bell state is increased above 90% using temporal gating to reject photons emitted at times when collection of uncorrelated light is more probable. A direct measurement of a CHSH Bell inequality is made showing a clear violation, highlighting that a quantum dot entangled photon source is suitable for communication exploiting nonlocal quantum correlations.

DOI
10.1103/physrevlett.102.030406

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Here we demonstrate, for the first time, violation of Bell's inequality using a triggered quantum dot photon-pair source without post-selection. Furthermore, the fidelity to the expected Bell state is increased above 90% using temporal gating to reject photons emitted at times when collection of uncorrelated light is more probable. A direct measurement of a CHSH Bell inequality is made showing a clear violation, highlighting that a quantum dot entangled photon source is suitable for communication exploiting nonlocal quantum correlations.
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