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A simple formula for the average gate fidelity of a quantum dynamical operation

Michael A. Nielsen
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Abstract

This note presents a simple formula for the average fidelity between a unitary quantum gate and a general quantum operation on a qudit, generalizing the formula for qubits found by Bowdrey et al [Phys. Lett. A 294, 258 (2002)]. This formula may be useful for experimental determination of average gate fidelity. We also give a simplified proof of a formula due to Horodecki et al [Phys. Rev. A 60, 1888 (1999)], connecting average gate fidelity to entanglement fidelity.

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Michael A. Nielsen. 2002-05-12. A simple formula for the average gate fidelity of a quantum dynamical operation. https://doi.org/10.1016/s0375-9601(02)01272-0

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