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arXiv · 1204.2473

A limit formula for the quantum fidelity

Gaetana Spedalieri·Christian Weedbrook·Stefano Pirandola
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Abstract

Quantum fidelity is a central tool in quantum information, quantifying how much two quantum states are similar. Here we propose a limit formula for the quantum fidelity between a mixed state and a pure state. As an example of an application, we apply this formula to the case of multimode Gaussian states, achieving a simple expression in terms of their first and second-order statistical moments.

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Gaetana Spedalieri, Christian Weedbrook, Stefano Pirandola. 2012-04-11. A limit formula for the quantum fidelity. https://doi.org/10.1088/1751-8113/46/2/025304

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