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arXiv · 0803.3947

Evolution of entanglement within classical light states

R. Mark Stevenson·Andrew J. Hudson·Anthony J. Bennett·Robert J. Young·Christine A. Nicoll·David A. Ritchie·Andrew J. Shields
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Abstract

We investigate the evolution of quantum correlations over the lifetime of a multi-photon state. Measurements reveal time-dependent oscillations of the entanglement fidelity for photon pairs created by a single semiconductor quantum dot. The oscillations are attributed to the phase acquired in the intermediate, non-degenerate, exciton-photon state and are consistent with simulations. We conclude that emission of photon pairs by a typical quantum dot with finite polarisation splitting is in fact entangled in a time-evolving state, and not classically correlated as previously regarded.

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R. Mark Stevenson, Andrew J. Hudson, Anthony J. Bennett, Robert J. Young, Christine A. Nicoll, David A. Ritchie, Andrew J. Shields. 2008-03-27. Evolution of entanglement within classical light states. https://doi.org/10.1103/physrevlett.101.170501

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