title: Unitary transformations can be distinguished locally.
abstract: We show that, in principle, N-partite unitary transformations can be perfectly discriminated under local operations and classical communication despite their nonlocal properties. Based on this result, some related topics, including the construction of the appropriate quantum circuit together with the extension to general completely positive trace preserving operations, are discussed.
authors.affiliation: Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China. xfzhou@mail.ustc.edu.cn
authors.forename: Xiang-Fa
authors.initials: XF
authors.lastname: Zhou
authors.forename: Yong-Sheng
authors.initials: YS
authors.lastname: Zhang
authors.forename: Guang-Can
authors.initials: GC
authors.lastname: Guo