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Fidelity balance in quantum operations

Konrad Banaszek
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Abstract

I derive a tight bound between the quality of estimating the state of a single copy of a $d$-level system, and the degree the initial state has to be altered in course of this procedure. This result provides a complete analytical description of the quantum mechanical trade-off between the information gain and the quantum state disturbance expressed in terms of mean fidelities. I also discuss consequences of this bound for quantum teleportation using nonmaximally entangled states.

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Konrad Banaszek. 2000-05-03. Fidelity balance in quantum operations. https://doi.org/10.1103/physrevlett.86.1366

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