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Related papers: Quantum entanglement in phase space

200 papers

We study the detection of continuous-variable entanglement, for which most of the existing methods designed so far require a full specification of the devices, and we present protocols for entanglement detection in a scenario where the…

Quantum Physics · Physics 2021-05-19 Paolo Abiuso , Stefan Bäuml , Daniel Cavalcanti , Antonio Acín

We study the continuous variable entanglement of a system of two particles under the influence of Earth's gravitational field. We determine a phase-space description of this bipartite system by calculating its Wigner function and verify its…

General Relativity and Quantum Cosmology · Physics 2016-07-28 Rui Alves , Catarina Bastos , Orfeu Bertolami

In contrast to abstract statistical analyses in the literature, we present a concrete physical diagrammatic model of entanglement characterization and measure with its underlying discrete phase-space physics. This paper serves as a…

Quantum Physics · Physics 2023-05-30 Felix A. Buot

Genuine entanglement identification of large scale systems is crucial for quantum computation, quantum communication and quantum learning advantage. In contrast to experiments, where noisy intermediate-scale programmable photonic quantum…

Quantum Physics · Physics 2025-12-01 Xiao-yu Chen

We propose to detect quantum entanglement by a condition of local measurments. We find that this condition can detect efficiently the pure entangled states for both discrete and continuous variable systems. It does not depend on…

Quantum Physics · Physics 2015-05-30 Qing Xie , X. -X. Wu , X. -M. Ding , W. -L. Yang , R. -H. Yue , H. Fan

We present practical methods to measure entanglement for quantum simulators that can be realized with trapped ions, cold atoms, and superconducting qubits. Focussing on long- and short-range Ising-type Hamiltonians, we introduce schemes…

Quantum Physics · Physics 2016-03-23 O. Marty , M. Cramer , M. B. Plenio

An extension to computational mechanics complexity measure is proposed in order to tackle quantum states complexity quantification. The method is applicable to any $n-$partite state of qudits through some simple modifications. A Werner…

Computational Physics · Physics 2011-10-28 Yuri Campbell , José Roberto Castilho Piqueira

A sufficient condition for entanglement in two-mode continuous systems is constructed based on interference visibility and the uncertainty of the total particle number. The observables to be measured (particle numbers and particle number…

Quantum Physics · Physics 2007-05-23 Geza Toth , Christoph Simon , Juan Ignacio Cirac

We develop a new entanglement measure by extending Jaeger's Minkowskian norm entanglement measure. This measure can be applied to a much wider class of multipartite mixed states, although still "quasi" in the sense that it is still…

Quantum Physics · Physics 2009-11-11 Jing Zhang , Chun-Wen Li , Re-Bing Wu , Tzyh-Jong Tarn , Jian-Wu Wu

Quantumness and separability criteria for continuous variable systems are discussed for the case of a noncommutative (NC) phase-space. In particular, the quantum nature and the entanglement configuration of NC two-mode Gaussian states are…

Quantum Physics · Physics 2015-10-13 Alex E. Bernardini , Catarina Bastos , Orfeu Bertolami , Nuno C. Dias , João N. Prata

We extend the definition of entanglement witnesses based on structure factors to the case in which the position of the scatterers is quantized. This allows us to study entanglement detection in hybrid systems. We provide several examples…

Quantum Physics · Physics 2015-06-19 Massimo Borrelli , Matteo Rossi , Chiara Macchiavello , Sabrina Maniscalco

Quantum entanglement plays a key role in quantum computation and quantum information processing. It is of great significance to find efficient and experimentally friend separability criteria to detect entanglement. In this paper, we firstly…

Quantum Physics · Physics 2024-05-09 Yiding Wang , Tinggui Zhang , Xiaofen Huang , Shao-Ming Fei

We consider entanglement detection for quantum key distribution systems that use two signal states and continuous variable measurements. This problem can be formulated as a separability problem in a qubit-mode system. To verify…

Quantum Physics · Physics 2007-05-23 Johannes Rigas , Otfried Gühne , Norbert Lütkenhaus

We study the Wigner function of phase-locked nondegenerate optical parametric oscillator and find the signatures of both phase-locking and self-pulsing phenomena in phase space. We also analyze the problem of continuous-variable…

Quantum Physics · Physics 2007-05-23 N. H. Adamyan , S. B. Manvelyan , G. Yu. Kryuchkyan

We present an entanglement criterion for two mode squeezed states which relies on particle counting only. The proposed inequality is optimal for the state under consideration and robust against particle losses up to 2/3. As it does not…

Quantum Physics · Physics 2008-09-16 Christine A. Muschik , Eugene S. Polzik , J. Ignacio Cirac

Classical surfaces in phase space correspond to quantum states in Hilbert space. Subsystems specify factor spaces of the Hilbert space. An entangled state corresponds semiclassically to a surface that cannot be decomposed into a product of…

Quantum Physics · Physics 2007-05-23 A. M. Ozorio de Almeida

We suggest an experimentally realizable scheme to test entanglement of a mixed Gaussian continuous variable state. We find that the entanglement condition is simplified for the family of Gaussian states which are relevant to experimental…

Quantum Physics · Physics 2007-05-23 M. S. Kim , Jinhyoung Lee

Entanglement detection is essential in quantum information science and quantum many-body physics. It has been proved that entanglement exists almost surely for a random quantum state, while the realizations of effective entanglement…

Quantum Physics · Physics 2022-12-02 Pengyu Liu , Zhenhuan Liu , Shu Chen , Xiongfeng Ma

Historically, the completeness of quantum theory has been questioned using the concept of bipartite continuous variable entanglement. The non-classical correlations (entanglement) between the two subsystems imply that the observables of one…

Quantum Gases · Physics 2011-12-21 C. Gross , H. Strobel , E. Nicklas , T. Zibold , N. Bar-Gill , G. Kurizki , M. K. Oberthaler

We present several measurement schemes for accessing separability criteria for continuous-variable bipartite quantum systems. Starting from moments of the bosonic mode operators, criteria suitable to witness entanglement are expressed in…

Quantum Physics · Physics 2023-08-28 Célia Griffet , Tobias Haas , Nicolas J. Cerf