English
Related papers

Related papers: Time-Continuous Bell Measurements

200 papers

A general matrix approach to study entangled states is presented, based on operator completeness relations. Bases of unitary operators are considered, with focus on irreducible representations of groups. Bell measurements for teleportation…

Quantum Physics · Physics 2009-11-06 G. M. D'Ariano , P. Lo Presti , M. F. Sacchi

We detail and extend the results of [Milman {\it et al.}, Phys. Rev. Lett. {\bf 99}, 130405 (2007)] on Bell-type inequalities based on correlations between measurements of continuous observables performed on trapped molecular systems. We…

Quantum Physics · Physics 2019-04-04 P. Milman , A. Keller , E. Charron , O. Atabek

We report a quantum teleportation experiment in which nonlinear interactions are used for the Bell state measurements. The experimental results demonstrate the working principle of irreversibly teleporting an unknown arbitrary quantum state…

Quantum Physics · Physics 2009-11-06 Yoon-Ho Kim , Sergei P. Kulik , Yanhua Shih

A Bell inequality is a fundamental test to rule out local hidden variable model descriptions of correlations between two physically separated systems. There have been a number of experiments in which a Bell inequality has been violated…

In this paper, we consider a two-qubit system undergoing continuous-time measurements. In presence of multiple channels, we provide sufficient conditions on the continuous feedback control law ensuring almost sure exponential convergence to…

Optimization and Control · Mathematics 2019-03-19 Weichao Liang , Nina H. Amini , Paolo Mason

A solid state device to discriminate all the four Bell states is proposed. The device is composed of controlled absorption crystals, rotators, and retarders. The controlled absorption, where the state of one photon affects the absorption of…

Quantum Physics · Physics 2007-05-23 A. Tomita

Bell-state projections serve as a fundamental basis for most quantum communication and computing protocols today. However, with current Bell-state measurement schemes based on linear optics, only two of four Bell states can be identified,…

Quantum Physics · Physics 2023-09-06 Matthias J. Bayerbach , Simone E. D'Aurelio , Peter van Loock , Stefanie Barz

We show how Bell observables on a bipartite quantum system can be obtained by local observables via a controlled-unitary transformation. For continuous variables this result holds for the Bell observable corresponding to the…

Quantum Physics · Physics 2007-05-23 Giacomo Mauro D'Ariano , Paolo Perinotti

Two important ingredients necessary for obtaining Bell nonlocal correlations between two spatially separated parties are an entangled state shared between them and an incompatible set of measurements employed by each of them. We focus on…

Quantum Physics · Physics 2025-05-26 Priya Ghosh , Chirag Srivastava , Swati Choudhary , Ujjwal Sen

We discuss recent developments in measurement protocols that generate quantum entanglement between two remote qubits, focusing on the theory of joint continuous detection of their spontaneous emission. We consider a device geometry similar…

Bell tests---the experimental demonstration of a Bell inequality violation---are central to understanding the foundations of quantum mechanics, underpin quantum technologies, and are a powerful diagnostic tool for technological developments…

Many quantum information protocols require a Bell-state measurement of entangled systems. Most optical Bell-state measurements utilize two-photon interference at a beam splitter. By creating polarization-entangled photons with spontaneous…

Quantum Physics · Physics 2009-11-07 S. P. Walborn , W. A. T. Nogueira , S. Pádua , C. H. Monken

The generation of long-lived entanglement on an optical clock transition is a key requirement to unlocking the promise of quantum metrology. Arrays of neutral atoms constitute a capable quantum platform for accessing such physics, where…

Atomic Physics · Physics 2022-08-12 Nathan Schine , Aaron W. Young , William J. Eckner , Michael J. Martin , Adam M. Kaufman

Based on the Bell theorem, it has been believed that a theoretical computation of the Bell correlation requires explicit use of an entangled state. Such a physical superposition of light waves occurs in the downconverter sources used in…

Quantum Physics · Physics 2021-01-14 Louis Sica

We show how to estimate a broad class of multipartite entanglement measures from Bell basis measurement data. In addition to lowering the experimental requirements relative to previously known methods of estimating these measures, our…

Quantum Physics · Physics 2023-07-12 Jacob L. Beckey , G. Pelegrí , Steph Foulds , Natalie J. Pearson

Entanglement plays a fundamental role in quantum physics and information processing. Here, we develop an unbiased estimator for mixed-state entanglement in the few-shot scenario and directly estimate it using random unitary evolution in a…

Quantum Physics · Physics 2024-07-09 Gong-Chu Li , Lei Chen , Si-Qi Zhang , Xu-Song Hong , You Zhou , Geng Chen , Chuan-Feng Li , Guang-Can Guo

We analyze nonclassical correlations between outcomes of measurements conducted on two spatial radiation modes. These correlations cannot be simulated with statistical mixtures of coherent states or, more generally, with non-negative…

Quantum Physics · Physics 2022-07-01 V. S. Kovtoniuk , I. S. Yeremenko , S. Ryl , W. Vogel , A. A. Semenov

We have theoretically investigated the possibility of using any of several continuous-variable Bell-type inequalities - for which the dichotomic measurements are achieved with coarse-grained quadrature (homodyne) measurements - in a…

Quantum Physics · Physics 2018-12-12 William N. Plick , Francesco Arzani , Nicolas Treps , Eleni Diamanti , Damian Markham

We consider dynamics of hidden variables for measurements in a generalized bell-type model for a single spin using natural assumptions. The evolution of the system, which can be expressed as dynamic chaos is studied. The equilibrium state…

Quantum Physics · Physics 2008-12-31 Yu. I. Bogdanov

The efficiency of a Bell-state measurement on photon pairs is bound to 50\,\% due to the number of Bell states that can be distinguished using linear optics. Here we present the implementation of a protocol that allows us to distinguish all…