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Related papers: Extremal covariant measurements

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We consider the problem of discriminating qubit states that are sent over a quantum channel and derive a necessary and sufficient condition for an optimal measurement to be preserved by the channel. We apply the result to the…

Quantum Physics · Physics 2020-07-07 Spiros Kechrimparis , Joonwoo Bae

In quantum theory general measurements are described by so-called Positive Operator-Valued Measures (POVMs). We show that in $d$-dimensional quantum systems an application of depolarizing noise with constant (independent of $d$) visibility…

Quantum Physics · Physics 2025-01-17 Michał Kotowski , Michał Oszmaniec

To mitigate dissipative effects from environmental interactions and efficiently stabilize quantum states, time-optimal control has emerged as an effective strategy for open quantum systems. This paper extends the framework by incorporating…

Quantum Physics · Physics 2025-08-25 Yunyan Lee , Ian R. Petersen , Daoyi Dong

Quantum state tomography seeks to reconstruct an unknown state from measurement statistics. A finite measurement (POVM) is \emph{pure-state informationally complete} (PSI-Complete) if the outcome probabilities determine any pure state up to…

Quantum Physics · Physics 2025-11-13 Dan Edidin , Ivan Gonzalez , Itzhak Tamo

A Positive Operator Valued Measure (POVM) is a map $F:\mathcal{B}(X)\to\mathcal{L}_s^+(\mathcal{H})$ from the Borel $\sigma$-algebra of a topological space $X$ to the space of positive self-adjoint operators on a Hilbert space…

Functional Analysis · Mathematics 2018-04-03 Roberto Beneduci

Peculiarities of multiqubit measurement are for the most part similar to peculiarities of measurement for qudit -- quantum object with finite-dimensional Hilbert space. Three different interpretations of measurement concept are analysed.…

Quantum Physics · Physics 2024-06-13 Constantin Usenko

We discuss a possibility to build a programmable quantum measurement device (a "quantum multimeter"). That is, a device that would be able to perform various desired generalized, positive operator value measure (POVM) measurements depending…

Quantum Physics · Physics 2013-05-29 Miloslav Dusek , Vladimir Buzek

This paper develops new extremal principles of variational analysis that are motivated by applications to constrained problems of stochastic programming and semi-infinite programming without smoothness and/or convexity assumptions. These…

Optimization and Control · Mathematics 2020-07-23 Boris S. Mordukhovich , Pedro Pérez-Aros

The structure of covariant instruments is studied and a general structure theorem is derived. A detailed characterization is given to covariant instruments in the case of an irreducible representation of a locally compact group.

Mathematical Physics · Physics 2009-10-16 Claudio Carmeli , Teiko Heinosaari , Alessandro Toigo

Informationally complete measurements on a quantum system allow to estimate the expectation value of any arbitrary operator by just averaging functions of the experimental outcomes. We show that such kind of measurements can be achieved…

Quantum Physics · Physics 2007-05-23 G. M. D'Ariano , P. Perinotti , M. F. Sacchi

Evaluating the amount of information obtained from non-orthogonal quantum states is an important topic in the field of quantum information. The commonly used evaluation method is Holevo bound, which only provides a loose upper bound for…

Quantum Physics · Physics 2021-09-27 Wei Li , Shengmei Zhao

It is well known that the space of invariant probability measures for transitive sub-shifts of finite type is a Poulsen simplex. In this article we prove that in the non-compact setting, for a large family of transitive countable Markov…

Dynamical Systems · Mathematics 2021-08-16 Godofredo Iommi , Anibal Velozo

We propose a scheme that can realize a class of positive-operator-valued measures (POVMs) by performing a sequence of projective measurements on the original system, in the sense that for an arbitrary input state the probability…

Quantum Physics · Physics 2007-05-23 Guoming Wang , Mingsheng Ying

We study the problem of separating the data produced by a given quantum measurement (on states from a memoryless source which is unknown except for its average state), described by a positive operator valued measure (POVM), into a…

Quantum Physics · Physics 2009-11-07 Andreas Winter

A solution to the second measurement problem, determining what prior microscopic properties can be inferred from measurement outcomes ("pointer positions"), is worked out for projective and generalized (POVM) measurements, using consistent…

Quantum Physics · Physics 2017-09-20 Robert B. Griffiths

The space of positive operator-valued measures on the Borel sets of a compact (or even locally compact) Hausdorff space with values in the algebra of linear operators acting on a d-dimensional Hilbert space is studied from the perspectives…

Quantum Physics · Physics 2015-05-30 Douglas Farenick , Sarah Plosker , Jerrod Smith

We consider measurements, described by a positive-operator-valued measure (POVM), whose outcome probabilities determine an arbitrary pure state of a D-dimensional quantum system. We call such a measurement a pure-state informationally…

Quantum Physics · Physics 2009-11-10 Steven T. Flammia , Andrew Silberfarb , Carlton M. Caves

I give a first characterization of the class of generalized measurements that can be exactly realized on a pair of qudits encoded in indistinguishable particles, by using only linear elements and particle detectors. Two immediate results…

Quantum Physics · Physics 2009-11-07 John Calsamiglia

Recently a problem concerning the equivalence of joint measurability and coexistence of quantum observables was solved [15]. In this paper we generalize two known joint measurability results from sharp observables to the class of extreme…

Quantum Physics · Physics 2015-08-19 Erkka Haapasalo , Juha-Pekka Pellonpää , Roope Uola

Measurement in quantum mechanics is notoriously unpredictable. The uncertainty in quantum measurement can arise from the noncommutativity between the state and the measurement basis which is intrinsically quantum, but it may also be of…

Quantum Physics · Physics 2024-12-17 Agung Budiyono