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Interference of Quantum Channels

Daniel K. L. Oi
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Abstract

We show how interferometry can be used to characterise certain aspects of general quantum processes, in particular, the coherence of completely positive maps. We derive a measure of coherent fidelity, maximum interference visibility and the closest unitary operator to a given physical process under this measure.

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Daniel K. L. Oi. 2003-04-14. Interference of Quantum Channels. https://doi.org/10.1103/physrevlett.91.067902

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