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Quantum Electronics and Laser Science Conference

Simple experimental generation of a four-photon cluster state and distinguishing classes of genuine four-qubit entanglement using witness operators

Yuuki Tokunaga, Shin Kuwashiro, Takashi Yamamoto, Masato Koashi, Nobuyuki Imoto

Published May 1, 2007• 0 citations
Publisher

Abstract

We experimentally demonstrate a simple scheme for generating a four-photon cluster state. We show that the produced state has genuine four-qubit entanglement which is discriminated from a class including GHZ and W types of entanglement.
DOI
10.1109/qels.2007.4431704

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We experimentally demonstrate a simple scheme for generating a four-photon entangled cluster state with fidelity over 0.860+/-0.015. We show that the fidelity is high enough to guarantee that the produced state is distinguished from Greenberger-Horne-Zeilinger, W, and Dicke types of genuine four-qubit entanglement. We also demonstrate basic operations of one-way quantum computing using the produced state and show that the output state fidelities surpass classical bounds, which indicates that the entanglement in the produced state essentially contributes to the quantum operation.
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