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Demonstration of Non-Deterministic Quantum Logic Operations using Linear Optical Elements

T. B. Pittman·B. C. Jacobs·J. D. Franson
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Abstract

Knill, Laflamme, and Milburn recently showed that non-deterministic quantum logic operations could be performed using linear optical elements, additional photons (ancilla), and post-selection based on the output of single-photon detectors [Nature 409, 46 (2001)]. Here we report the experimental demonstration of two logic devices of this kind, a destructive controlled-NOT (CNOT) gate and a quantum parity check. These two devices can be combined with a pair of entangled photons to implement a conventional (non-destructive) CNOT that succeeds with a probability of 1/4.

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T. B. Pittman, B. C. Jacobs, J. D. Franson. 2001-11-02. Demonstration of Non-Deterministic Quantum Logic Operations using Linear Optical Elements. https://doi.org/10.1103/physrevlett.88.257902

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