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Entanglement Is Not Necessary for Perfect Discrimination between Unitary Operations

Runyao Duan·Yuan Feng·Mingsheng Ying
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Abstract

We show that a unitary operation (quantum circuit) secretely chosen from a finite set of unitary operations can be determined with certainty by sequentially applying only a finite amount of runs of the unknown circuit. No entanglement or joint quantum operations is required in our scheme. We further show that our scheme is optimal in the sense that the number of the runs is minimal when discriminating only two unitary operations.

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Runyao Duan, Yuan Feng, Mingsheng Ying. 2007-03-26. Entanglement Is Not Necessary for Perfect Discrimination between Unitary Operations. https://doi.org/10.1103/physrevlett.98.100503

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