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arXiv · 1303.0271

An entangling quantum-logic gate operated with an ultrabright single photon-source

O. Gazzano·M. P. Almeida·A. K. Nowak·S. L. Portalupi·A. Lemaître·I. Sagnes·A. G. White.·P. Senellart
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Abstract

We demonstrate unambiguous entangling operation of a photonic quantum-logic gate driven by an ultrabright solid-state single-photon source. Indistinguishable single photons emitted by a single semiconductor quantum dot in a micropillar optical cavity are used as target and control qubits. For a source brightness of 0.56 collected photons-per-pulse, the measured truth table has an overlap with the ideal case of 68.4%, increasing to 73.0% for a source brightness of 0.17 photons- per-pulse. The gate is entangling: at a source brightness of 0.48, the Bell-state fidelity is above the entangling threshold of 50%, and reaches 71.0% for a source brightness of 0.15.

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O. Gazzano, M. P. Almeida, A. K. Nowak, S. L. Portalupi, A. Lemaître, I. Sagnes, A. G. White., P. Senellart. 2013-03-04. An entangling quantum-logic gate operated with an ultrabright single photon-source. https://doi.org/10.1103/physrevlett.110.250501

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