Unambiguous discrimination of sequences of quantum states
Abstract
We consider the problem of determining the state of an unknown quantum sequence without error. The elements of the given sequence are drawn with equal probability from a known set of linearly independent pure quantum states with the property that their mutual inner products are all real and equal. This problem can be posed as an instance of unambiguous state discrimination where the states correspond to that of all possible sequences having the same length as the given one. We calculate the optimum probability by solving the optimality conditions of a semidefinite program. The optimum value is achievable by measuring individual members of the sequence, and no collective measurement is necessary.
Keywords
Cite
@article{arxiv.2402.06365,
title = {Unambiguous discrimination of sequences of quantum states},
author = {Tathagata Gupta and Shayeef Murshid and Somshubhro Bandyopadhyay},
journal= {arXiv preprint arXiv:2402.06365},
year = {2024}
}
Comments
v1:17 pages; v2: published version, 19 pages, expanded introduction, better organized proof of the main result, and several minor edits to improve clarity