Ultimate limits of approximate unambiguous discrimination

Quantum hypothesis testing is an important tool for quantum information processing. Two main strategies have been widely adopted: in a minimum error discrimination strategy, the average error probability is minimized; while in an unambiguous discrimination strategy, an inconclusive decision (abstent...

Full description

Bibliographic Details
Main Author: Quntao Zhuang
Format: Article
Language:English
Published: American Physical Society 2020-11-01
Series:Physical Review Research
Online Access:http://doi.org/10.1103/PhysRevResearch.2.043276
_version_ 1827285892889313280
author Quntao Zhuang
author_facet Quntao Zhuang
author_sort Quntao Zhuang
collection DOAJ
description Quantum hypothesis testing is an important tool for quantum information processing. Two main strategies have been widely adopted: in a minimum error discrimination strategy, the average error probability is minimized; while in an unambiguous discrimination strategy, an inconclusive decision (abstention) is allowed to vanish any possibility of errors when a conclusive result is obtained. In both scenarios, the testing between quantum states is relatively well understood, for example, the ultimate limits of the performance are established decades ago; however, the testing between quantum channels is less understood. Although the ultimate limit of minimum error discrimination between channels has been explored recently, the corresponding limit of unambiguous discrimination is unknown. In this paper, we formulate an approximate unambiguous discrimination scenario, and derive the ultimate limits of the performance for both states and channels. In particular, in the channel case, our lower bound of the inconclusive probability holds for arbitrary adaptive sensing protocols. For the special class of “teleportation-covariant” channels, the lower bound is achievable with maximum entangled inputs and no adaptive strategy is necessary.
first_indexed 2024-04-24T10:22:17Z
format Article
id doaj.art-0d8a997fd87d4dd88f44349797b3dc5a
institution Directory Open Access Journal
issn 2643-1564
language English
last_indexed 2024-04-24T10:22:17Z
publishDate 2020-11-01
publisher American Physical Society
record_format Article
series Physical Review Research
spelling doaj.art-0d8a997fd87d4dd88f44349797b3dc5a2024-04-12T17:04:20ZengAmerican Physical SocietyPhysical Review Research2643-15642020-11-012404327610.1103/PhysRevResearch.2.043276Ultimate limits of approximate unambiguous discriminationQuntao ZhuangQuantum hypothesis testing is an important tool for quantum information processing. Two main strategies have been widely adopted: in a minimum error discrimination strategy, the average error probability is minimized; while in an unambiguous discrimination strategy, an inconclusive decision (abstention) is allowed to vanish any possibility of errors when a conclusive result is obtained. In both scenarios, the testing between quantum states is relatively well understood, for example, the ultimate limits of the performance are established decades ago; however, the testing between quantum channels is less understood. Although the ultimate limit of minimum error discrimination between channels has been explored recently, the corresponding limit of unambiguous discrimination is unknown. In this paper, we formulate an approximate unambiguous discrimination scenario, and derive the ultimate limits of the performance for both states and channels. In particular, in the channel case, our lower bound of the inconclusive probability holds for arbitrary adaptive sensing protocols. For the special class of “teleportation-covariant” channels, the lower bound is achievable with maximum entangled inputs and no adaptive strategy is necessary.http://doi.org/10.1103/PhysRevResearch.2.043276
spellingShingle Quntao Zhuang
Ultimate limits of approximate unambiguous discrimination
Physical Review Research
title Ultimate limits of approximate unambiguous discrimination
title_full Ultimate limits of approximate unambiguous discrimination
title_fullStr Ultimate limits of approximate unambiguous discrimination
title_full_unstemmed Ultimate limits of approximate unambiguous discrimination
title_short Ultimate limits of approximate unambiguous discrimination
title_sort ultimate limits of approximate unambiguous discrimination
url http://doi.org/10.1103/PhysRevResearch.2.043276
work_keys_str_mv AT quntaozhuang ultimatelimitsofapproximateunambiguousdiscrimination