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arXiv · 1704.01348

Implementation of a quantum controlled-SWAP gate with photonic circuits

Takafumi Ono·Ryo Okamoto·Masato Tanida·Holger F. Hofmann·Shigeki Takeuchi
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Abstract

Quantum information science addresses how the processing and transmission of information are affected by uniquely quantum mechanical phenomena. Combination of two-qubit gates has been used to realize quantum circuits, however, scalability is becoming a critical problem. The use of three-qubit gates may simplify the structure of quantum circuits dramatically. Among them, the controlled-SWAP (Fredkin) gates are essential since they can be directly applied to important protocols, e.g., error correction, fingerprinting, and optimal cloning. Here we report a realization of the Fredkin gate for photonic qubits. We achieve a fidelity of 0.85 in the computational basis and an output state fidelity of 0.81 for a 3-photon Greenberger-Horne-Zeilinger state. The estimated process fidelity of 0.77 indicates that our Fredkin gate can be applied to various quantum tasks.

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Takafumi Ono, Ryo Okamoto, Masato Tanida, Holger F. Hofmann, Shigeki Takeuchi. 2017-04-05. Implementation of a quantum controlled-SWAP gate with photonic circuits. https://arxiv.org/abs/1704.01348

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