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arXiv:0802.1441 · Physical Review Letters

Demonstration of a Quantum Controlled-NOT Gate in the Telecommunications Band

Jun Chen, Joseph B. Altepeter, Milja Medić, Kim Fook Lee, Burç Gökden, Robert H. Hadfield, Sae Woo Nam, Prem Kumar

Published Apr 4, 2008• 92 citations
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Abstract

We present the first quantum controlled-not (cnot) gate realized using a fiber-based indistinguishable photon-pair source in the 1.55 microm telecommunications band. Using this free-space cnot gate, all four Bell states are produced and fully characterized by performing quantum-state tomography, demonstrating the gate's unambiguous entangling capability and high fidelity. Telecom-band operation makes this cnot gate particularly suitable for quantum-information-processing tasks that are at the interface of quantum communication and linear optical quantum computing.

DOI
10.1103/physrevlett.100.133603

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