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Related papers: Tomographic test of Bell's inequality

200 papers

Optical homodyne detection is examined in view of joint probability distribution. It is usually discussed that the relative phase between independent laser fields are localized by photon-number measurements in interference experiments such…

Quantum Physics · Physics 2010-09-07 Toru Kawakubo , Katsuji Yamamoto

We suggest and demonstrate a tomographic method to fully characterize homodyne detectors at the quantum level. The operator measure associated with the detector is expanded in the quadrature basis and probed with a set of coherent states.…

Quantum Physics · Physics 2024-02-15 Samuele Grandi , Alessandro Zavatta , Marco Bellini , Matteo G. A. Paris

We derive a simple formula for the transformation of an arbitrary covariance matrix of (n+2) bosonic modes under general Bell-like detections, where the last two modes are combined in an arbitrary beam splitter (i.e., with arbitrary…

Quantum Physics · Physics 2014-10-13 Gaetana Spedalieri , Carlo Ottaviani , Stefano Pirandola

We propose a feasible approach to test Bell's inequality with the experimentally-demonstrated circuit QED system, consisting of two well-separated superconducting charge qubits (SCQs) dispersively coupled to a common one-dimensional…

Quantum Physics · Physics 2011-01-14 Hao Yuan , L. F. Wei , J. S. Huang , X. H. Wang , Vlatko Vedral

Homodyne detection is one of the ways to circumvent the standard quantum limit for a gravitational wave detector. In this paper it will be shown that the same quantum-non-demolition effect using homodyne detection can be realized by…

General Relativity and Quantum Cosmology · Physics 2020-07-06 K. Somiya

We study the hypothesis testing problem of distinguishing between correlated thermal noise and uncorrelated thermal noise of the same average energy on $K$ detectors in asymptotic asymmetric hypothesis testing. We compare the performance of…

Quantum Physics · Physics 2025-09-19 Janis Nötzel , Pere Munar-Vallespir

Traditional method for measuring continuous-variable quantum entanglement relies on balanced homodyne detections, which are sensitive to vacuum quantum noise coupled in through losses resulted from many factors such as detector's quantum…

Quantum Physics · Physics 2020-05-06 Jiamin Li , Yuhong Liu , Nan Huo , Liang Cui , Sheng Feng , Xiaoying Li , Z. Y. Ou

Photons of a laser beam driving the upper motional sideband of an optomechanical cavity can decay into photon-phonon pairs by means of an optomechanical parametric process. The phononic state can subsequently be mapped to a photonic state…

Quantum Physics · Physics 2016-02-24 V. Caprara Vivoli , T. Barnea , C. Galland , N. Sangouard

We derive tight quadratic inequalities for all kinds of hybrid separable-inseparable $n$-particle density operators on an arbitrary dimensional space. This methodology enables us to truly derive a tight quadratic inequality as tests for…

Quantum Physics · Physics 2009-11-07 Koji Nagata , Masato Koashi , Nobuyuki Imoto

Nonlocal quantum realizations, certified by the violation of a Bell inequality, are core resources for device-independent quantum information processing. Although proof-of-principle experiments demonstrating device-independent quantum…

The problem of closing the detection loophole with asymmetric systems, such as entangled atom-photon pairs, is addressed. We show that, for the Bell inequality I_3322, a minimal detection efficiency of 43% can be tolerated for one of the…

Quantum Physics · Physics 2009-11-13 Nicolas Brunner , Nicolas Gisin , Valerio Scarani , Christoph Simon

We identify what ideal correlated photon number states are to required to maximize the discrepancy between local realism and quantum mechanics when a quadrature homodyne phase measurement is used. Various Bell inequality tests are…

Quantum Physics · Physics 2009-11-06 W. J. Munro

We compare the standard 50%-efficient single beam splitter method for Bell-state measurement to a proposed 75%-efficient auxiliary-photon-enhanced scheme [W. P. Grice, Phys. Rev. A 84, 042331 (2011)] in light of realistic conditions. The…

Homo- and heterodyne detection are fundamental techniques for measuring propagating electromagnetic fields. However, applying these techniques to stationary fields confined in cavities poses a challenge. As a way to overcome this challenge,…

Quantum Physics · Physics 2024-08-08 Ingrid Strandberg , Axel Eriksson , Baptiste Royer , Mikael Kervinen , Simone Gasparinetti

A single photon, delocalized over two optical modes, is characterized by means of quantum homodyne tomography. The reconstructed four-dimensional density matrix extends over the entire Hilbert space and thus reveals, for the first time,…

Quantum Physics · Physics 2009-11-10 S. A. Babichev , J. Appel , A. I. Lvovsky

Although our understanding of Bell's theorem and experimental techniques to test it have improved over the last 40 years, thus far all Bell tests have suffered at least from the detection or the locality loophole. Most photonic Bell tests…

Quantum Physics · Physics 2015-02-19 Falk Töppel , Magdalena Stobińska

We show that the use of probabilistic noiseless amplification in entangled coherent state-based schemes for the test of quantum non locality provides substantial advantages. The threshold amplitude to falsify a Bell-CHSH non locality test,…

Quantum Physics · Physics 2013-05-14 G. Torlai , G. McKeown , P. Marek , R. Filip , H. Jeong , M. Paternostro , G. De Chiara

We show that homodyne measurements can be used to demonstrate violations of Bell's inequality with Gaussian states, when the local rotations used for these types of tests are implemented using nonlinear unitary operations. We reveal that…

Quantum Physics · Physics 2009-11-13 M. Paternostro , H. Jeong , T. C. Ralph

This paper deals with a non-parametric problem coming from physics, namely quantum tomography. That consists in determining the quantum state of a mode of light through a homodyne measurement. We apply several model selection procedures:…

Statistics Theory · Mathematics 2007-12-19 Jonas Kahn

The homodyne detection is one of the most basic tools for identifying the quantum state of light. It has been used to detect useful non-local properties, such as entanglement for the quantum teleportation and distillability of a secret key…

Quantum Physics · Physics 2022-12-22 Go Kato , Kiyoshi Tamaki , Masaki Owari , Koji Azuma