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Tomography of Quantum Operations

G. M. D'Ariano·P. Lo Presti
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Abstract

Quantum operations describe any state change allowed in quantum mechanics, including the evolution of an open system or the state change due to a measurement. In this letter we present a general method based on quantum tomography for measuring experimentally the matrix elements of an arbitrary quantum operation. As input the method needs only a single entangled state. The feasibility of the technique for the electromagnetic field is shown, and the experimental setup is illustrated based on homodyne tomography of a twin-beam.

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G. M. D'Ariano, P. Lo Presti. 2000-12-14. Tomography of Quantum Operations. https://doi.org/10.1103/physrevlett.86.4195

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