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Related papers: Unambiguous discrimination of mixed quantum states

200 papers

Error probability is a popular and well-studied optimization criterion in discriminating non-orthogonal quantum states. It captures the threat from an adversary who can only query the actual state once. However, when the adversary is able…

Quantum Physics · Physics 2015-05-11 Weien Chen , Yongzhi Cao , Hanpin Wang , Yuan Feng

We derive the optimal measurement for quantum state discrimination without a priori probabilities, i.e. in a minimax strategy instead of the usually considered Bayesian one. We consider both minimal-error and unambiguous discrimination…

Quantum Physics · Physics 2025-04-02 Giacomo Mauro D'Ariano , Massimiliano Federico Sacchi , Jonas Kahn

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

Given a mixture of states, finding a way to optimally discriminate its elements is a prominent problem in quantum communication theory. In this paper, we will address mixtures of density operators that are unitarily equivalent via elements…

Mathematical Physics · Physics 2024-02-09 Alberto Acevedo , Janek Wehr

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

Quantum state discrimination is a fundamental concept in quantum information theory, which refers to a class of techniques to identify a specific quantum state through a positive operator-valued measure. In this work, we investigate how…

Quantum Physics · Physics 2025-07-09 Hyunho Cha , Jungwoo Lee

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

In this paper, we shall show that the question of quanum state unambiguous discrimination can be solved by reducing it to the known problem of quantum states filtering.

Quantum Physics · Physics 2015-09-01 Xiaohua Wu , Yu Shaolan , Zhou Tao

We investigate the extent to which we can establish whether or not two quantum systems have been prepared in the same state. We investigate the possibility of universal unambiguous state comparison. We show that it is impossible to…

Quantum Physics · Physics 2009-11-07 Stephen M. Barnett , Anthony Chefles , Igor Jex

We study the measurement for the unambiguous discrimination of two mixed quantum states that are described by density operators $\rho_1$ and $\rho_2$ of rank d, the supports of which jointly span a 2d-dimensional Hilbert space. Based on two…

Quantum Physics · Physics 2009-11-13 Ulrike Herzog

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 show a geometric formulation for minimum-error discrimination of qubit states, that can be applied to arbitrary sets of qubit states given with arbitrary a priori probabilities. In particular, when qubit states are given with equal…

Quantum Physics · Physics 2015-06-04 Joonwoo Bae , Won-Young Hwang

We study the procedure for sequential unambiguous state discrimination. A qubit is prepared in one of two possible states, and measured by two observers Bob and Charlie sequentially. A necessary condition for the state to be unambiguously…

Quantum Physics · Physics 2013-12-02 Chao-Qian Pang , Fu-Lin Zhang , Li-Fang Xu , Mai-Lin Liang , Jing-Ling Chen

The separability detecting problem of mixed states is one of the fundamental problems in quantum information theory. In the last 20 years, almost all methods are based on the sufficient or necessary conditions for entanglement. However, in…

Quantum Physics · Physics 2020-07-15 Ying Li , Guyan Ni

Given a finite set of linearly independent quantum states, an observer who examines a single quantum system may sometimes identify its state with certainty. However, unless these quantum states are orthogonal, there is a finite probability…

Quantum Physics · Physics 2009-09-25 Asher Peres , Daniel Terno

Distinguishing different quantum states is a fundamental task having practical applications for information processing. Despite the efforts devoted so far, however, strategies for optimal discrimination are known only for specific examples.…

Quantum Physics · Physics 2015-06-11 Joonwoo Bae

We present a general scheme to realize the POVMs for the unambiguous discrimination of quantum states. For any set of pure states it enables us to set up a feasible linear optical circuit to perform their optimal discrimination, if they are…

Quantum Physics · Physics 2016-08-16 Bing He , János A. Bergou

The problem of discriminating the state of a quantum system among a number of hypothetical states is usually addressed under the assumption that one has perfect knowledge of the possible states of the system. In this thesis, I analyze the…

Quantum Physics · Physics 2014-07-18 Gael Sentís

We propose an optimal discrimination scheme for a case of four linearly independent nonorthogonal symmetric quantum states, based on linear optics only. The probability of discrimination is in agreement with the optimal probability for…

Quantum Physics · Physics 2009-11-13 O. Jiménez , X. Sánchez-Lozano , A. Delgado , C. Saavedra

We discuss the problem of designing unambiguous programmable discriminators for any n unknown quantum states in an m-dimensional Hilbert space. The discriminator is a fixed measurement that has two kinds of input registers: the program…

Quantum Physics · Physics 2007-05-23 Chi Zhang , Mingsheng Ying , Bo Qiao