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Related papers: On compatibility of binary qubit measurements

200 papers

Contextuality is a signature of operational nonclassicality in the outcome statistics of an experiment. This notion of nonclassicality applies to a breadth of physical phenomena. Here, we establish its relation to two fundamental…

Quantum Physics · Physics 2020-01-07 Armin Tavakoli , Roope Uola

Unambiguous measurements play an important role in quantum information, with applications ranging from quantum key distribution to quantum state reconstruction. Recently, such measurements have also been used in quantum algorithms based on…

Quantum Physics · Physics 2025-11-05 Quentin Buzet , André Chailloux

We demonstrate that quantum incompatibility can always be detected by means of a state discrimination task with partial intermediate information. This is done by showing that only incompatible measurements allow for an efficient use of…

Quantum Physics · Physics 2019-04-09 Claudio Carmeli , Teiko Heinosaari , Alessandro Toigo

Quantum measurements with feed-forward are crucial components of fault-tolerant quantum computers. We show how the error rate of such a measurement can be directly estimated by fitting the probability that successive randomly compiled…

Quantum Physics · Physics 2025-02-04 Darian McLaren , Matthew A. Graydon , Ali Assem Mahmoud , Joel J. Wallman

We introduce a framework for simulating quantum measurements based on classical processing of a set of accessible measurements. Well-known concepts such as joint measurability and projective simulability naturally emerge as particular cases…

Quantum Physics · Physics 2017-09-27 Leonardo Guerini , Jessica Bavaresco , Marcelo Terra Cunha , Antonio Acín

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

We consider the task of deciding whether an unknown qubit state falls in a prescribed neighborhood of a reference state. We assume that several copies of the unknown state are given and apply a unitary operation pairwise on them combined…

Quantum Physics · Physics 2018-08-27 Orsolya Kálmán , Tamás Kiss

Incompatible, i.e. non-jointly measurable quantum measurements are a necessary resource for many information processing tasks. It is known that increasing the number of distinct measurements usually enhances the incompatibility of a…

Quantum Physics · Physics 2023-09-28 Lucas Tendick , Hermann Kampermann , Dagmar Bruß

In non-relativistic quantum mechanics, measurements performed by separate observers are modeled via tensor products. In Algebraic Quantum Field Theory, though, local observables corresponding to space-like separated parties are just…

Quantum Physics · Physics 2013-05-30 Miguel Navascues , David Perez-Garcia

These two accompanying papers treat two mode entanglement for systems of identical massive bosons and the relationship to spin squeezing and other quantum correlation effects. Entanglement is a key quantum feature of composite systems where…

Quantum Physics · Physics 2016-06-01 Bryan Dalton , John Goold , Barry Garraway , Margaret Reid

Quantum correlation includes quantum entanglement and quantum discord. Both entanglement and discord have a common necessary condition--------quantum coherence or quantum superposition. In this paper, we attempt to give an alternative…

Quantum Physics · Physics 2014-09-23 Chang-shui Yu , Yang Zhang , Haiqing Zhao

We are interested in the problem of characterizing the correlations that arise when performing local measurements on separate quantum systems. In a previous work [Phys. Rev. Lett. 98, 010401 (2007)], we introduced an infinite hierarchy of…

Quantum Physics · Physics 2009-01-16 Miguel Navascues , Stefano Pironio , Antonio Acin

If a measurement is made on one half of a bipartite system, then, conditioned on the outcome, the other half has a new reduced state. If these reduced states defy classical explanation -- that is, if shared randomness cannot produce these…

Quantum Physics · Physics 2018-02-13 Carl A. Miller , Roger Colbeck , Yaoyun Shi

A primary requirement for a robust and unconditionally secure quantum network is the establishment of quantum nonlocal correlations over a realistic channel. While loophole-free tests of Bell nonlocality allow for entanglement certification…

It is well known that when two or more quantum measurements suffer from imperfections they may lose their incompatibility. For a quantum system of finite dimension d we study the incompatibility of all projective measurements subjected to…

Quantum Physics · Physics 2025-02-11 Pavel Sekatski

We describe a particular class of pairs of quantum observables which are extremal in the convex set of all pairs of compatible quantum observables. The pairs in this class are constructed as uniformly noisy versions of two mutually unbiased…

Quantum Physics · Physics 2019-07-24 Claudio Carmeli , Gianni Cassinelli , Alessandro Toigo

We introduce a measure of average dimensionality (or coherence) for high-dimensional quantum devices. This includes sets of quantum measurements, steering assemblages, and quantum channels. For measurements and channels, our measure…

Quantum Physics · Physics 2023-06-22 Thomas Cope , Roope Uola

Joint measurements of two-Pauli observables are a powerful tool for both the control and protection of quantum information. By following a simple recipe for measurement choices, single- and two- qubit rotations using two-Pauli parity and…

Quantum Physics · Physics 2024-11-07 Matthew Brooks , Charles Tahan

We study the problem of mapping an unknown mixed quantum state onto a known pure state without the use of unitary transformations. This is achieved with the help of sequential measurements of two non-commuting observables only. We show that…

Quantum Physics · Physics 2009-11-11 L. Roa , M. L. Ladron de Guevara , A. Delgado , A. Klimov

The notion of incompatibility of measurements in quantum theory is in stark contrast with the corresponding classical perspective, where all physical observables are jointly measurable. It is of interest to examine if the results of two or…

Quantum Physics · Physics 2015-01-29 H. S. Karthik , A. R. Usha Devi , A. K. Rajagopal