English
Related papers

Related papers: Complete analysis for three-qubit mixed-state disc…

200 papers

We present a way of identifying all kinds of entanglement for three-qubit pure states in terms of the expectation values of Pauli operators. The necessary and sufficient conditions to classify the fully separable, biseparable, and genuine…

Quantum Physics · Physics 2015-06-12 Ming-Jing Zhao , Ting-Gui Zhang , Xianqing Li-Jost , Shao-Ming Fei

In this paper, the distinguishability of multipartite geometrically uniform quantum states obtained from a single reference state is studied in the symmetric subspace. We specially focus our attention on the unitary transformation in a way…

Quantum Physics · Physics 2015-03-24 M. A. Jafarizadeh , P. Sadeghi , d. Akhgar , P. Mahmoudi

In the present paper I formulate a framework that accommodates many unambiguous discrimination problems. I show that the prior information about any type of constituent (state, channel, or observable) allows us to reformulate the…

Quantum Physics · Physics 2010-03-15 Michal Sedlák

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

Quantum state elimination measurements tell us what states a quantum system does not have. This is different from state discrimination, where one tries to determine what the state of a quantum system is, rather than what it is not. Apart…

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

The discrimination of quantum states is a central problem in quantum information science and technology. Meanwhile, partial post-selection has emerged as a valuable tool for quantum state engineering. In this work, we bring these two areas…

Quantum Physics · Physics 2026-04-14 Qipeng Qian , Christos N. Gagatsos

Quantum bits, or qubits, are the fundamental building blocks of present quantum computers. Hence, it is important to be able to characterize the state of a qubit as accurately as possible. By evaluating the qubit characterization problem…

Quantum Physics · Physics 2024-02-27 Bacui Li , Lorcan O. Conlon , Ping Koy Lam , Syed M. Assad

We consider the problem of determining the mixed quantum state of a large but finite number of identically prepared quantum systems from data obtained in a sequence of ideal (von Neumann) measurements, each performed on an individual copy…

Quantum Physics · Physics 2009-11-10 Franz Embacher , Heide Narnhofer

We study the geometric measure of entanglement (GM) of pure symmetric states related to rank-one positive-operator-valued measures (POVMs) and establish a general connection with quantum state estimation theory, especially the maximum…

Quantum Physics · Physics 2011-01-17 Lin Chen , Huangjun Zhu , Tzu-Chieh Wei

We investigate entanglement in two-qubit systems using a geometric representation based on the minimum of essential parameters. The latter is achieved by requiring subsystems with the same entropy, regardless of whether the state of the…

Quantum Physics · Physics 2024-12-24 Salvio Luna-Hernandez , Claudia Quintana , Oscar Rosas-Ortiz

We propose an experimental setup that is capable of unambiguously discriminating any pair of linearly independent single photon polarization qubits, about which we don't have any knowledge except that an extra pair of these unknown states…

Quantum Physics · Physics 2007-09-05 Bing He , Janos A. Bergou , Yuhang Ren

An important task for quantum information processing is optimal discrimination between two non-orthogonal quantum states, which until now has only been realized optically. Here, we present and compare experimental realizations of optimal…

We discuss the problem of estimating a general (mixed) qubit state. We give the optimal guess that can be inferred from any given set of measurements. For collective measurements and for a large number $N$ of copies, we show that the error…

Quantum Physics · Physics 2009-11-10 E. Bagan , M. Baig , R. Munoz-Tapia , A. Rodriguez

We present the results of generalized measurements of optical polarization designed to provide one of three or four distinct outcomes. This has allowed us to discriminate between nonorthogonal polarization states with an error probability…

This paper presents a detailed study of constrained quantization for both finite and infinite discrete probability distributions supported on subsets of the real line. Under specific geometric constraints - namely, a semicircular arc and…

We show how one can solve the problem of discriminating between qubit states. We use the quantum state discrimination duality theorem and the Bloch sphere representation of qubits which allows for an easy geometric and analytical…

Quantum Physics · Physics 2010-06-28 M. E. Deconinck , B. M. Terhal

Intrinsic randomness is generated when a quantum state is measured in any basis in which it is not diagonal. In an adversarial scenario, we quantify this randomness by the probability that a correlated eavesdropper could correctly guess the…

Quantum Physics · Physics 2026-02-19 Fionnuala Curran

Quantum state discrimination is a fundamental primitive in quantum statistics where one has to correctly identify the state of a system that is in one of two possible known states. A programmable discrimination machine performs this task…

Quantum Physics · Physics 2015-05-19 G. Sentís , E. Bagan , J. Calsamiglia , R. Munoz-Tapia

Despite the successful experimental generation and verification of genuine multipartite entanglement, several existing entanglement measures remain insufficient to reliably capture its presence. In this study, we overcome this challenge by…

Quantum Physics · Physics 2025-10-20 Shruti Aggarwal