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arXiv · 0802.1441

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

Jun Chen·Joseph B. Altepeter·Milja Medic·Kim Fook Lee·Burc Gokden·Robert H. Hadfield·Sae Woo Nam·Prem Kumar
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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 $μ$m 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.

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Jun Chen, Joseph B. Altepeter, Milja Medic, Kim Fook Lee, Burc Gokden, Robert H. Hadfield, Sae Woo Nam, Prem Kumar. 2008-02-11. Demonstration of a Quantum Controlled-NOT Gate in the Telecom Band. https://doi.org/10.1103/physrevlett.100.133603

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