English
Related papers

Related papers: Quantum measurement and uncertainty relations in p…

200 papers

A method for photon linear polarization determination based on the measurement of the asymmetry of pairs produced by polarized photons in single crystals within the optimal intervals of pair particles energies is proposed. In difference to…

High Energy Physics - Experiment · Physics 2009-10-31 A. B. Apyan , R. O. Avakian , S. M. Darbinian , K. A. Ispirian , S. P. Taroian

Quantum descriptions of polarization show the rich degrees of freedom underlying classical light. While changes in polarization of light are well-described classically, a full quantum description of polarimetry, which characterizes…

Quantum Physics · Physics 2020-04-22 Aaron Z. Goldberg

The problem of measuring an unbounded system attribute near a singularity has been discussed. Lenses have been introduced as formal objects to study increasingly precise measurements around the singularity and a specific family of lenses…

General Mathematics · Mathematics 2020-07-13 Swagatam Sen

Motivated by quantum resource theories, we introduce a notion of incompatibility for quantum measurements relative to a reference basis. The notion arises by considering states diagonal in that basis and investigating whether probability…

Quantum Physics · Physics 2019-08-21 Georgios Styliaris , Paolo Zanardi

Coherence and correlations represent two related properties of a compound system. The system can be, for instance, the polarization of a photon, which forms part of a polarization-entangled two-photon state, or the spatial shape of a…

Quantum Physics · Physics 2015-12-01 Jiří Svozilík , Adam Vallés , Jan Peřina , Juan P. Torres

Uncertainty relation is not only of fundamental importance to quantum mechanics, but also crucial to the quantum information technology. Recently, majorization formulation of uncertainty relations (MURs) have been widely studied, ranging…

Measurements are central in all quantitative sciences, and a fundamental challenge is to make observations without systematic measurement errors. This holds in particular for quantum information processing, where other error sources, such…

According to quantum theory, two ensembles of quantum systems that are described by the same density operator are indistinguishable. For example, unpolarized light can be obtained either by an incoherent mixture of two orthogonal pure…

Quantum Physics · Physics 2011-09-07 Guilherme P. Temporão , Jean Pierre von der Weid

Decoherence is widely felt to have something to do with the quantum measurement problem, but getting clear on just what is made difficult by the fact that the "measurement problem", as traditionally presented in foundational and…

Quantum Physics · Physics 2015-06-03 David Wallace

We report on the first experimental realization of the entanglement witness for polarization entangled photons. It represents a recently discovered significant quantum information protocol which is based on few local measurements. The…

Quantum Physics · Physics 2013-05-29 M. Barbieri , F. De Martini , G. Di Nepi , P. Mataloni , G. M. D'Ariano , C. Macchiavello

Conventional polarimetry, including schemes leveraging entangled light, characterizes optical samples through linear transformations of polarization states. We introduce a two-photon probing approach in which both photons of an entangled…

We report on the quantification of entanglement by means of entanglement measures on a four- and a six- qubit cluster state realized by using photons entangled both in polarization and linear momentum. This paper also addresss the question…

Quantum Physics · Physics 2011-03-23 H. Wunderlich , G. Vallone , P. Mataloni , M. B. Plenio

We study quantum measurement retrodiction using the principle of minimum change. For quantum-to-classical measurement channels, we show that all standard quantum divergences select the same retrodictive update, yielding a unique and…

Quantum Physics · Physics 2025-11-27 Jiaxi Kuang , Kensei Torii , Francesco Buscemi

We report an experimental investigation of the role of measurement in quantum metrology when the states of the probes are mixed. In particular, we investigated optimized local measurements and general global projective measurements,…

Quantum Physics · Physics 2021-02-22 R. S. Piera , S. P. Walborn , G. H. Aguilar

A novel solution to the quantum measurement problem is presented by using a new asymmetric equation that is complementary to the Schr\"odinger equation. Solved for the hydrogen atom, the new equation describes the temporal and spatial…

General Physics · Physics 2024-10-25 Z. E. Musielak

We present the uncertainty relation for the characteristic functions (ChUR) of the quantum mechanical position and momentum probability distributions. This inequality is more general than the Heisenberg Uncertainty Relation, and is…

Quantum Physics · Physics 2016-02-17 Łukasz Rudnicki , Daniel S. Tasca , Stephen P. Walborn

Proximity measurements probe whether pairs of particles are close to one another. We consider the impact of post-selected random proximity measurements on a quantum fluid of many distinguishable particles. We show that such measurements…

Quantum Physics · Physics 2025-08-01 Pushkar Mohile , Paul M. Goldbart

We review the state of the art for measuring the X-ray polarization of neutron stars. We discuss how valuable precision measurements of the degree and position angle of polarization as a function of energy and, where relevant, of pulse…

Astrophysics · Physics 2007-05-23 M. C. Weisskopf , R. F. Elsner , D. Hanna , V. M. Kaspi , S. L. O'Dell , G. G. Pavlov , B. D. Ramsey

We address potential deviations of radiation field from the bosonic behaviour and employ local quantum estimation theory to evaluate the ultimate bounds to precision in the estimation of these deviations using quantum-limited measurements…

Quantum Physics · Physics 2014-07-09 Giovanni De Cillis , Matteo G. A. Paris

We propose a class of incompatibility measures for quantum observables based on quantifying the effect of a measurement of one observable on the statistics of the outcomes of another. Specifically, for a pair of observables $A$ and $B$ with…

Quantum Physics · Physics 2014-09-30 Prabha Mandayam , M. D. Srinivas