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Using Qubits to Measure Fidelity in Mesoscopic Systems

G. B. Lesovik·F. Hassler·G. Blatter
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Abstract

We point out the similarities in the definition of the `fidelity' of a quantum system and the generating function determining the full counting statistics of charge transport through a quantum wire and suggest to use flux- or charge qubits for their measurement. As an application we use the notion of fidelity within a first-quantized formalism in order to derive new results and insights on the generating function of the full counting statistics.

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G. B. Lesovik, F. Hassler, G. Blatter. 2006-12-29. Using Qubits to Measure Fidelity in Mesoscopic Systems. https://doi.org/10.1103/physrevlett.96.106801

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