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Related papers: On the generalization of quantum state comparison

200 papers

Quantum mechanics forbids deterministic discrimination among non-orthogonal states. Nonetheless, the capability to distinguish nonorthogonal states unambiguously is an important primitive in quantum information processing. In this work, we…

Quantum Physics · Physics 2016-08-16 Masoud Mohseni , Aephraim M. Steinberg , János A. Bergou

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…

Quantum Physics · Physics 2024-05-27 Tathagata Gupta , Shayeef Murshid , Somshubhro Bandyopadhyay

Given $n$ linearly independent pure states and their prior probabilities, we study the problem of optimum unambiguous discrimination of these states. We derive the properties of the optimum solution and the equations that must be satisfied…

Quantum Physics · Physics 2013-05-29 Shengshi Pang , Shengjun Wu

Roa et al. showed that quantum state discrimination between two nonorthogonal quantum states does not require quantum entanglement but quantum dissonance only. We find that quantum coherence can also be utilized for unambiguous quantum…

Quantum Physics · Physics 2021-08-10 Sunho Kim , Longsuo Li , Asutosh Kumar , Chunhe Xiong , Sreetama Das , Ujjwal Sen , Arun Kumar Pati , Junde Wu

We study the problem of discriminating between non-orthogonal quantum states with least probability of error. We demonstrate that this problem can be simplified if we solve for the error itself rather than solving directly for the optimal…

Quantum Physics · Physics 2009-11-10 Kieran Hunter

We study an optimized measurement which discriminates N mixed quantum states occurring with given prior robabilities. The measurement yields the maximum achievable confidence for each of the N conclusive outcomes, thereby keeping the…

Quantum Physics · Physics 2015-06-04 Ulrike Herzog

It is a central fact in quantum mechanics that non-orthogonal states cannot be distinguished perfectly. This property ensures the security of quantum key distribution. It is therefore an important task in quantum communication to design and…

Quantum Physics · Physics 2023-11-27 Lorcan O. Conlon , Falk Eilenberger , Ping Koy Lam , Syed M. Assad

Sequential methods for quantum hypothesis testing offer significant advantages over fixed-length approaches, which rely on a predefined number of state copies. Despite their potential, these methods remain underexplored for unambiguous…

Quantum Physics · Physics 2025-11-26 Jordi Pérez-Guijarro , Alba Pagès-Zamora , Javier R. Fonollosa

We address a problem of identifying a given pure state with one of two reference pure states, when no classical knowledge on the reference states is given, but a certain number of copies of them are available. We assume the input state is…

Quantum Physics · Physics 2009-11-11 A. Hayashi , M. Horibe , T. Hashimoto

The impossibility of deterministic and error-free discrimination among nonorthogonal quantum states lies at the core of quantum theory and constitutes a primitive for secure quantum communication. Demanding determinism leads to errors,…

Quantum Physics · Physics 2021-12-21 M. A. Solís-Prosser , O. Jiménez , A. Delgado , L. Neves

We investigate the optimal convex approximation of the quantum state with respect to a set of available states. By isometric transformation, we have presented the general mathematical model and its solutions together with a triple…

Quantum Physics · Physics 2020-06-17 Xiao-Bin Liang , Bo Li , Liang Huang , Biao-Liang Ye , Shao-Ming Fei , Shi-Xiang Huang

We investigate quantum state discrimination with confidentiality. $N$ observers share a given quantum state belonging to a finite set of known states. The observers want to determine the state as accurately as possible and send a…

Quantum Physics · Physics 2015-06-30 Kenji Nakahira , Tsuyoshi Sasaki Usuda , Kentaro Kato

The problem of discriminating with minimum error between two mixed quantum states is reviewed, with emphasize on the detection operators necessary for performing the measurement. An analytical result is derived for the minimum probability…

Quantum Physics · Physics 2009-11-10 Ulrike Herzog

We address the problem of distinguishing among a finite collection of quantum states, when the states are not entirely known. For completely specified states, necessary and sufficient conditions on a quantum measurement minimizing the…

Quantum Physics · Physics 2009-11-11 Noam Elron , Yonina C. Eldar

We address a broad class of optimization problems of finding quantum measurements, which includes the problems of finding an optimal measurement in the Bayes criterion and a measurement maximizing the average success probability with a…

Quantum Physics · Physics 2015-06-23 Kenji Nakahira , Kentaro Kato , Tsuyoshi Sasaki Usuda

We address perfect discrimination of two separable states. When available states are restricted to separable states, we can theoretically consider a larger class of measurements than the class of measurements allowed in quantum theory. The…

Quantum Physics · Physics 2020-10-08 Hayato Arai , Yuuya Yoshida , Masahito Hayashi

We study the estimation of the overlap between two unknown pure quantum states of a finite dimensional system, given $M$ and $N$ copies of each type. This is a fundamental primitive in quantum information processing that is commonly…

We show that the quantum measurement known as the pretty good measurement can be used to identify an unknown quantum state picked from any set of $n$ mixed states that have pairwise fidelities upper-bounded by a constant below 1, given…

Quantum Physics · Physics 2019-11-11 Ashley Montanaro

We consider the problem of discriminating between states of a specified set with maximum confidence. For a set of linearly independent states unambiguous discrimination is possible if we allow for the possibility of an inconclusive result.…

Quantum Physics · Physics 2007-05-23 Sarah Croke , Erika Andersson , Stephen M. Barnett , Claire R. Gilson , John Jeffers

Recently the problem of Unambiguous State Discrimination (USD) of mixed quantum states has attracted much attention. So far, bounds on the optimum success probability have been derived [1]. For two mixed states they are given in terms of…

Quantum Physics · Physics 2008-06-04 Philippe Raynal , Norbert Lütkenhaus