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arXiv · 0705.3991

Macroscopic Greenberger-Horne-Zeilinger and W States in Flux Qubits

Mun Dae Kim·Sam Young Cho
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Abstract

We investigate two types of genuine three-qubit entanglement, known as the Greenberger-Horne-Zeilinger(GHZ) and W states, in a macroscopic quantum system. Superconducting flux qubits are considered theoretically in order to generate such states. A phase coupling is proposed to offer enough strength of interactions between qubits. While an excited state can be the W state, the GHZ state is formed at the ground state of the three flux qubits. The GHZ and W states are shown to be robust against external flux fluctuations for feasible experimental realizations.

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Mun Dae Kim, Sam Young Cho. 2008-02-23. Macroscopic Greenberger-Horne-Zeilinger and W States in Flux Qubits. https://doi.org/10.1103/physrevb.77.100508

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