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Multiparticle entanglement with quantum logic networks: Application to cold trapped ions

Marek Sasura·Vladimir Buzek
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Abstract

We show how to construct a multi-qubit control gate on a quantum register of an arbitrary size N. This gate performs a single-qubit operation on a specific qubit conditioned by the state of other N-1 qubits. We provide an algorithm how to build up an array of networks consisting of single-qubit rotations and multi-qubit control-NOT gates for the synthesis of an arbitrary entangled quantum state of N qubits. We illustrate the algorithm on a system of cold trapped ions. This example illuminates the efficiency of the direct implementation of the multi-qubit CNOT gate compared to its decomposition into a network of two-qubit CNOT gates.

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Marek Sasura, Vladimir Buzek. 2001-03-13. Multiparticle entanglement with quantum logic networks: Application to cold trapped ions. https://doi.org/10.1103/physreva.64.012305

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