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Title: Unambiguous discrimination of mixed states: A description based on system-ancilla coupling

Abstract

We propose a general description for the unambiguous discrimination of mixed states according to the system-environment coupling, and present a procedure to reduce this to a standard semidefinite programming problem. In the two-state case, we introduce the canonical vectors and partly simplify the problem to the case of discrimination between pairs of canonical vectors. By considering the positivity of the 2x2 matrices, we obtain a series of new upper bounds for the total success probability, which depends on both the prior probabilities and specific state structures.

Authors:
; ;  [1]
  1. Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, Anhui 230026 (China)
Publication Date:
OSTI Identifier:
20982483
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.052314; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOUND STATE; COUPLING; MATRICES; MIXED STATE; PARTICLE DISCRIMINATION; PROBABILITY; PROGRAMMING

Citation Formats

Zhou, Xiang-Fa, Zhang, Yong-Sheng, and Guo, Guang-Can. Unambiguous discrimination of mixed states: A description based on system-ancilla coupling. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.052314.
Zhou, Xiang-Fa, Zhang, Yong-Sheng, & Guo, Guang-Can. Unambiguous discrimination of mixed states: A description based on system-ancilla coupling. United States. doi:10.1103/PHYSREVA.75.052314.
Zhou, Xiang-Fa, Zhang, Yong-Sheng, and Guo, Guang-Can. Tue . "Unambiguous discrimination of mixed states: A description based on system-ancilla coupling". United States. doi:10.1103/PHYSREVA.75.052314.
@article{osti_20982483,
title = {Unambiguous discrimination of mixed states: A description based on system-ancilla coupling},
author = {Zhou, Xiang-Fa and Zhang, Yong-Sheng and Guo, Guang-Can},
abstractNote = {We propose a general description for the unambiguous discrimination of mixed states according to the system-environment coupling, and present a procedure to reduce this to a standard semidefinite programming problem. In the two-state case, we introduce the canonical vectors and partly simplify the problem to the case of discrimination between pairs of canonical vectors. By considering the positivity of the 2x2 matrices, we obtain a series of new upper bounds for the total success probability, which depends on both the prior probabilities and specific state structures.},
doi = {10.1103/PHYSREVA.75.052314},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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