English

Discrimination with an error margin among three symmetric states of a qubit

Quantum Physics 2012-10-12 v2

Abstract

We consider a state discrimination problem which deals with settings of minimum-error and unambiguous discrimination systematically by introducing a margin for the probability of an incorrect guess. We analyze discrimination of three symmetric pure states of a qubit. The measurements are classified into three types, and one of the three types is optimal depending on the value of the error margin. The problem is formulated as one of semidefinite programming. Starting with the dual problem derived from the primal one, we analytically obtain the optimal success probability and the optimal measurement that attains it in each domain of the error margin. Moreover, we analyze the case of three symmetric mixed states of a qubit.

Keywords

Cite

@article{arxiv.1208.5090,
  title  = {Discrimination with an error margin among three symmetric states of a qubit},
  author = {H. Sugimoto and Y. Taninaka and A. Hayashi},
  journal= {arXiv preprint arXiv:1208.5090},
  year   = {2012}
}

Comments

8 pages, 1 figure, typos corrected, presentation improved