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A robust one-step catalytic machine for high fidelity anti-cloning and W-state generation in a multi-qubit system

Alexandra Olaya-Castro·Neil F. Johnson·Luis Quiroga
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Abstract

We propose a physically realizable machine which can either generate multiparticle W-like states, or implement high fidelity $1 \to M$ ($M=1,2,... \infty$) anti-cloning of an arbitrary qubit state, in a single step. Moreover this universal machine acts as a catalyst in that it is unchanged after either procedure, effectively resetting itself for its next operation. It also possesses an inherent {\em immunity} to decoherence. Most importantly in terms of practical multi-party quantum communication, the machine's robustness in the presence of decoherence actually {\em increases} as the number of qubits $M$ increases.

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Alexandra Olaya-Castro, Neil F. Johnson, Luis Quiroga. 2004-09-16. A robust one-step catalytic machine for high fidelity anti-cloning and W-state generation in a multi-qubit system. https://doi.org/10.1103/physrevlett.94.110502

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