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Related papers: Optimal unbiased state characterization

200 papers

This paper reports a novel method for supervised machine learning based on the mathematical formalism that supports quantum mechanics. The method uses projective quantum measurement as a way of building a prediction function. Specifically,…

Quantum Physics · Physics 2022-08-30 Fabio A. González , Vladimir Vargas-Calderón , Herbert Vinck-Posada

We describe a general methods to localize any sort of k-separability and therefore also the corresponding partial entanglement in genuinely multipartite mixed quantum states. Our methods are based exclusively on the known twopartite methods…

Quantum Physics · Physics 2010-03-02 Roman Gielerak Marek Sawerwain

The problem of unambiguously distinguishing among nonorthogonal but linearly independent quantum states can be solved by mapping the set of nonorthogonal quantum states onto a set of orthogonal ones, which can then be distinguished without…

Quantum Physics · Physics 2009-11-06 Yuqing Sun , Mark Hillery , Janos Bergou

We study the steerability for arbitrary dimensional bipartite systems based on the correlation matrices given by local special unitary groups. We present families of steering criteria for bipartite quantum states in terms of parameterized…

Quantum Physics · Physics 2023-12-12 Qing-Hua Zhang , Lemin Lai , Shao-Ming Fei

We present an alternative definition of quantum entanglement for bipartite system based on Bell inequality and operators' noncommutativity. A state is said to be entangled, if the maximum of CHSH expectation value $F_{\max}$ is obtain by…

Quantum Physics · Physics 2007-05-23 Li-Bin Fu , Jing-Ling Chen , Xian-Geng Zhao , Shi-Gang Chen

We employ a straightforward relation between mutually unbiased and Bell bases to extend the latter in terms of a direct construction for the former. We analyze in detail the properties of these new generalized Bell states, showing that they…

Quantum Physics · Physics 2009-10-23 A. B. Klimov , D. Sych , L. L. Sanchez-Soto , G. Leuchs

This paper investigates the problem of estimating biases affecting relative state measurements in a sensor network. Each sensor measures the relative states of its neighbors and this measurement is corrupted by a constant bias. We analyse…

Systems and Control · Computer Science 2019-05-23 Mingming Shi , Claudio De Persis , Pietro Tesi , Nima Monshizadeh

This paper studies the structural controllability of a class of uncertain switched linear systems, where the parameters of subsystems state matrices are either unknown or zero. The structural controllability is a generalization of the…

Systems and Control · Computer Science 2013-08-27 Xiaomeng Liu , Hai Lin , Ben M. Chen

Mutually unbiased bases (MUBs) play a key role in many protocols in quantum science, such as quantum key distribution. However, defining MUBs for arbitrary high-dimensional systems is theoretically difficult, and measurements in such bases…

Quantum Physics · Physics 2013-04-03 D. Giovannini , J. Romero , J. Leach , A. Dudley , A. Forbes , M. J. Padgett

Bound entangled states are states that are entangled but from which no entanglement can be distilled if all parties are allowed only local operations and classical communication. However, in creating these states one needs nonzero…

Quantum Physics · Physics 2009-11-10 Tzu-Chieh Wei , Joseph B. Altepeter , Paul M. Goldbart , William J. Munro

We analyze the problem of reconstructing an unknown quantum state of a multipartite system from repeated measurements of local observables. In particular, via a system-theoretic observability analysis, we show that, even when the initial…

Quantum Physics · Physics 2025-09-23 Marco Peruzzo , Tommaso Grigoletto , Francesco Ticozzi

We present a general necessary and sufficient criterion for the possibility of a state transformation from one mixed Gaussian state to another of a bi-partite continuous-variable system with two modes. The class of operations that will be…

Quantum Physics · Physics 2009-11-07 J. Eisert , M. B. Plenio

In this paper, we consider the problem of optimizing the worst-case behavior of a partially observed system. All uncontrolled disturbances are modeled as finite-valued uncertain variables. Using the theory of cost distributions, we present…

Optimization and Control · Mathematics 2023-02-21 Aditya Dave , Nishanth Venkatesh , Andreas A. Malikopoulos

A new hierarchy of separability conditions for bipartite states is obtained. All the conditions in the hierarchy are necessary for separability. The conditions are expressed in terms of higher powers of the density operator of the bipartite…

Quantum Physics · Physics 2010-06-10 S. Sivakumar

Based on the realignment moments of density matrix, we study parameterized entanglement criteria for bipartite and multipartite states. By adjusting the different parameter values, our criterion can detect not only bound entangled states,…

Quantum Physics · Physics 2025-10-13 Hui Zhao , Shu-Ying Zhuang , Naihuan Jing , Mei-Ming Zhang

We qualify the entanglement of arbitrary mixed states of bipartite quantum systems by comparing global and marginal mixednesses quantified by different entropic measures. For systems of two qubits we discriminate the class of maximally…

Quantum Physics · Physics 2007-05-23 Gerardo Adesso , Fabrizio Illuminati , Silvio De Siena

We present a generic study of unambiguous discrimination between two mixed quantum states. We derive operational optimality conditions and show that the optimal measurements can be classified according to their rank. In Hilbert space…

Quantum Physics · Physics 2010-03-10 M. Kleinmann , H. Kampermann , D. Bruss

In a 1991 paper, Asher Peres and the author theoretically analyzed a set of unentangled bipartite quantum states that could apparently be distinguished better by a global measurement than by any sequence of local measurements on the…

Quantum Physics · Physics 2007-05-23 William K. Wootters

Everett's concept of relative state can be viewed as a map that contains information about correlations between measurement outcomes on two quantum systems. We demonstrate how geometric properties of the relative state map can be used to…

Quantum Physics · Physics 2012-01-31 Pierre Rudolfsson , Erik Sjöqvist

We investigate generalized measurements, based on positive-operator-valued measures, and von Neumann measurements for the unambiguous discrimination of two mixed quantum states that occur with given prior probabilities. In particular, we…

Quantum Physics · Physics 2009-11-11 Ulrike Herzog , Janos A. Bergou