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arXiv · 0802.1930

Fidelity and Entanglement of a Spatially Extended Linear Three-Qubit Register

Roland Doll·Martijn Wubs·Sigmund Kohler·Peter Hanggi
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Abstract

We study decoherence of a three-qubit array coupled to substrate phonons. Assuming an initial three-qubit entangled state that would be decoherence-free for identical qubit positions, allows us to focus on non-Markovian effects of the inevitable spatial qubit separation. It turns out that the coherence is most affected when the qubits are regularly spaced. Moreover, we find that up to a constant scaling factor, two-qubit entanglement is not influenced by the presence f the third qubit, even though all qubits interact via the phonon field.

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Roland Doll, Martijn Wubs, Sigmund Kohler, Peter Hanggi. 2008-02-13. Fidelity and Entanglement of a Spatially Extended Linear Three-Qubit Register. https://arxiv.org/abs/0802.1930

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