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arXiv · 1009.2618

Solid-State Optimal Phase-Covariant Quantum Cloning Machine

Xin-Yu Pan·Gang-Qin Liu·Li-Li Yang·Heng Fan
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Abstract

Here we report an experimental realization of optimal phase-covariant quantum cloning machine with a single electron spin in solid state system at room temperature. The involved three states of two logic qubits are encoded physically in three levels of a single electron spin with two Zeeman sub-levels at a nitrogen-vacancy defect center in diamond. The preparation of input state and the phase-covariant quantum cloning transformation are controlled by two independent microwave fields. The average experimental fidelity reaches 85.2% which is very close to theoretical optimal fidelity 85.4% and is beyond the bound 83.3% of universal cloning.

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Xin-Yu Pan, Gang-Qin Liu, Li-Li Yang, Heng Fan. 2011-09-29. Solid-State Optimal Phase-Covariant Quantum Cloning Machine. https://doi.org/10.1063/1.3624595

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