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Quantum cloning machines for equatorial qubits

Heng Fan·Keiji Matsumoto·Xiang-Bin Wang·Miki Wadati
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Abstract

Quantum cloning machines for equatorial qubits are studied. For the case of 1 to 2 phase-covariant quantum cloning machine, we present the networks consisting of quantum gates to realize the quantum cloning transformations. The copied equatorial qubits are shown to be separable by using Peres-Horodecki criterion. The optimal 1 to M phase-covariant quantum cloning transformations are given.

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Heng Fan, Keiji Matsumoto, Xiang-Bin Wang, Miki Wadati. 2001-09-05. Quantum cloning machines for equatorial qubits. https://doi.org/10.1103/physreva.65.012304

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