arXiv:1303.0271 · Physical Review Letters

Entangling Quantum-Logic Gate Operated with an Ultrabright Semiconductor Single-Photon Source

Olivier Gazzano, Marcelo Pereira de Almeida, A. K. Nowak, Simone Luca Portalupi, Aristide Lemaître, Isabelle Sagnes, Andrew G. White, P. Senellart

Published Jun 17, 2013• 62 citations

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Abstract

We demonstrate the 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 photons per pulse, the measured truth table has an overlap with the ideal case of 68.4±0.5%, increasing to 73.0±1.6% 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±3.6% for a source brightness of 0.15.

DOI: 10.1103/physrevlett.110.250501

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