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arXiv · quant-ph/0601187

Improved fidelity of triggered entangled photons from single quantum dots

Robert J. Young·R. Mark Stevenson·Paola Atkinson·Ken Cooper·David A. Ritchie·Andrew J. Shields
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Abstract

We demonstrate the on-demand emission of polarisation-entangled photon pairs from the biexciton cascade of a single InAs quantum dot embedded in a GaAs/AlAs planar microcavity. Improvements in the sample design blue shifts the wetting layer to reduce the contribution of background light in the measurements. Results presented show that >70% of the detected photon pairs are entangled. The high fidelity of the (|HxxHx>+|VxxVx>)/2^0.5 state that we determine is sufficient to satisfy numerous tests for entanglement. The improved quality of entanglement represents a significant step towards the realisation of a practical quantum dot source compatible with applications in quantum information.

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Robert J. Young, R. Mark Stevenson, Paola Atkinson, Ken Cooper, David A. Ritchie, Andrew J. Shields. 2006-02-26. Improved fidelity of triggered entangled photons from single quantum dots. https://doi.org/10.1088/1367-2630%2F8%2F2%2F029

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