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arXiv · 1011.3806

Entanglement-fidelity relations for inaccurate ancilla-driven quantum computation

Tomoyuki Morimae·Jonas Kahn
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Abstract

It was shown in [T. Morimae, Phys. Rev. A {\bf81}, 060307(R) (2010)] that the gate fidelity of an inaccurate one-way quantum computation is upper bounded by a decreasing function of the amount of entanglement in the register. This means that a strong entanglement causes the low gate fidelity in the one-way quantum computation with inaccurate measurements. In this paper, we derive similar entanglement-fidelity relations for the inaccurate ancilla-driven quantum computation. These relations again imply that a strong entanglement in the register causes the low gate fidelity in the ancilla-driven quantum computation if the measurements on the ancilla are inaccurate.

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Tomoyuki Morimae, Jonas Kahn. 2010-11-16. Entanglement-fidelity relations for inaccurate ancilla-driven quantum computation. https://doi.org/10.1103/physreva.82.052314

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