Perfect distinguishability of quantum operations

Runyao Duan1, Yuan Feng, Mingsheng Ying

  • 1State Key Laboratory of Intelligent Technology and Systems, Tsinghua National Laboratory for Information Science and Technology, Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China. Runyao.Duan@uts.edu.au

Summary

Researchers identified conditions for perfectly distinguishing unknown quantum operations using a finite number of queries. An optimal protocol was designed, demonstrating perfect discrimination of two isometries is possible without extra systems or entanglement.

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