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Related papers: Bell Measurements and Observables

200 papers

We study the mathematical structure of superoperators describing quantum measurements, including the \emph{entangling measurement}--the generalization of the standard quantum measurement that results in entanglement between the measurable…

Quantum Physics · Physics 2009-11-10 Boris Grishanin , Victor Zadkov

The principle of teleportation can be used to perform a quantum computation even before its quantum input is defined. The basic idea is to perform the quantum computation at some earlier time with qubits which are part of an entangled…

Quantum Physics · Physics 2009-11-07 Caslav Brukner , Jian-Wei Pan , Christoph Simon , Gregor Weihs , Anton Zeilinger

Entanglement witnesses (EWs) are a collection of observables that can characterize separable states and, experimentally, estimating EWs can verify entangled states. In this work, we show that a fixed measurement setting on a multipartite…

Quantum Physics · Physics 2026-05-29 Jaemin Kim , Anindita Bera , Dariusz Chruściński , Joonwoo Bae

We give a description of the teleportation of an unknown quantum state which takes into account the action of the measuring device and manifestly avoids any reference to the postulate of the state vector collapse.

Quantum Physics · Physics 2009-11-07 P. Busch , G. Cassinelli , E. De Vito , P. Lahti , A. Levrero

Any Bell test consists of a sequence of measurements on a quantum state in space-like separated regions. Thus, a state is better than others for a Bell test when, for the optimal measurements and the same number of trials, the probability…

Quantum Physics · Physics 2009-11-11 Antonio Acin , Richard Gill , Nicolas Gisin

An algebraic approach to the study of entanglement entropy of quantum systems is reviewed. Starting with a state on a $C^*$-algebra, one can construct a density operator describing the state in the GNS representation state. Applications of…

Quantum Physics · Physics 2022-12-12 A. F. Reyes-Lega

We review the theory of entanglement measures, concentrating mostly on the finite dimensional two-party case. Topics covered include: single-copy and asymptotic entanglement manipulation; the entanglement of formation; the entanglement…

Quantum Physics · Physics 2011-07-06 Martin B. Plenio , S. Virmani

Quantum network protocols depend on the availability of shared entanglement. Given that entanglement generation and distribution are affected by noise, characterization of the shared entangled states is essential to bound the errors of the…

Quantum Physics · Physics 2025-10-31 Noah Kaufmann , Maria Quadeer , David Elkouss

Algebraic approach to quantum non - separability is applied to the case of two qubits. It is based on the partition of the algebra of observables into independent subalgebras and the tensor product structure of the Hilbert space is not…

Quantum Physics · Physics 2015-05-30 L. Derkacz , M. Gwozdz , L. Jakobczyk

We describe a procedure to create entangled history states and measurements that would enable one to check for temporal entanglement. The checks take the form of inequalities among observable quantities. They are similar in spirit, but…

Quantum Physics · Physics 2015-03-24 Jodan Cotler , Frank Wilczek

Employing mutually-commuting von Neumann algebras to represent the algebra of observables on quantum systems provides a framework for studying quantum information theory in systems with infinite degrees of freedom and quantum field theory,…

Quantum Physics · Physics 2026-04-21 Shuyuan Yang , Jinchuan Hou , Kan He

We push the limits of the direct use of partially pure entangled states to perform quantum teleportation by presenting several protocols in many different scenarios that achieve the optimal efficiency possible. We review and put in a single…

Quantum Physics · Physics 2013-07-11 Raphael Fortes , Gustavo Rigolin

We analyze the loss of fidelity in continuous variable teleportation due to non-maximal entanglement. It is shown that the quantum state distortions correspond to the measurement back-action of a field amplitude measurement. Results for…

Quantum Physics · Physics 2017-08-23 Holger F. Hofmann , Toshiki Ide , Takayoshi Kobayashi , Akira Furusawa

We derive tight Bell's inequalities for N>2 observers involving more than two alternative measurement settings. We give a necessary and sufficient condition for a general quantum state to violate the new inequalities. The inequalities are…

Quantum Physics · Physics 2009-11-10 Wieslaw Laskowski , Tomasz Paterek , Marek Zukowski , Caslav Brukner

We study entanglement activation in a generalized entanglement swapping process involving two Bell pairs and generalized measurements. The conventional understanding posits entangled measurements as both necessary and sufficient for…

Quantum Physics · Physics 2024-05-24 Pratapaditya Bej , Abhishek Banerjee

The ability to teleport entanglement through maximally entangled mixed states as defined by concurrence and linear entropy is studied. We show how the teleported entanglement depends on the quality of the quantum channel used, as defined…

Quantum Physics · Physics 2017-10-03 S. Campbell , M. Paternostro

A preliminary overview of measurement-based quantum computation in the setting of symmetry and topological phases of quantum matter is given. The underlying mechanism for universal quantum computation by teleportation or symmetry are…

Quantum Physics · Physics 2019-07-04 Dong-Sheng Wang

This paper presents a new measure of entanglement which can be employed for multipartite entangled systems. The classification of multipartite entangled systems based on this measure is considered. Two approaches to applying this measure to…

Quantum Physics · Physics 2018-08-20 Seyed Arash Sheikholeslam , Thomas Aaron Gulliver

We present a new paradigm for capturing the complementarity of two observables. It is based on the entanglement created by the interaction between the system observed and the two measurement devices used to measure the observables…

Quantum Physics · Physics 2014-01-29 Patrick J. Coles , Marco Piani

Bell inequalities can be studied both as constraints in the space of probability distributions and as expectation values of multipartite operators. The latter approach is particularly useful when considering outcomes as eigenvalues of…

Quantum Physics · Physics 2016-09-22 Daniel Alsina , Alba Cervera , Dardo Goyeneche , José I. Latorre , Karol Życzkowski