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Related papers: Entanglement versus Correlations in Spin Systems

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In this Letter we discuss the entanglement near a quantum phase transition by analyzing the properties of the concurrence for a class of exactly solvable models in one dimension. We find that entanglement can be classified in the framework…

Quantum Physics · Physics 2009-11-07 A. Osterloh , L. Amico , G. Falci , R. Fazio

In this paper, we study the entanglement between two-neighboring sites and the rest of the system in a simple quantum phase transition of 1D transverse field Ising model. We find that the entanglement shows interesting scaling and singular…

Quantum Physics · Physics 2009-11-13 Shi-Quan Su , Jun-Liang Song , Shi-Jian Gu

Entanglement is considered to be one of the most profound features of quantum mechanics. An entangled state of a system consisting of two subsystems cannot be described as a product of the quantum states of the two subsystems. In this sense…

Quantum Physics · Physics 2009-11-07 Brian Julsgaard , Alexander Kozhekin , Eugene S. Polzik

We propose a strategy to generate a many-body entangled state in a collection of randomly placed, dipolarly coupled electronic spins in the solid state. By using coherent control to restrict the evolution into a suitable collective…

Quantum Physics · Physics 2009-09-12 Paola Cappellaro , Mikhail D. Lukin

In this paper we address the question: where in configuration space is the entanglement between two particles located? We present a thought-experiment, equally applicable to discrete or continuous-variable systems, in which one or both…

Quantum Physics · Physics 2007-05-23 H. -C. Lin , A. J. Fisher

We briefly review the physics of gate operations between quantum dot spin-qubits and analyze the dynamics of quantum entanglement in such processes. The indistinguishable character of the electrons whose spins realize the qubits gives rise…

Condensed Matter · Physics 2007-05-23 John Schliemann , Daniel Loss

Quantum spins of mesoscopic size are a well-studied playground for engineering non-classical states. If the spin represents the collective state of an ensemble of qubits, its non-classical behavior is linked to entanglement between the…

We investigate numerically the time dependence of the multiple quantum coherences and entanglement in linear chains up to nine nuclear spins of 1/2 coupled by the dipole-dipole interactions. Two models are considered: (1) a spin chain with…

Quantum Physics · Physics 2009-11-13 G. B. Furman , V. M. Meerovich , V. L. Sokolovsky

The frame of classical probability theory can be generalized by enlarging the usual family of random variables in order to encompass nondeterministic ones: this leads to a frame in which two kinds of correlations emerge: the classical…

Quantum Physics · Physics 2007-05-23 E. G. Beltrametti , S. Bugajski

We consider two distant spin-$\frac{1}{2}$ particles (or qubits) and a number of interacting objects, all with the same value $S\gg1$ of their respective spin, distributed on a one-dimensional lattice (or large-$S$ spin chain). The quantum…

Quantum Physics · Physics 2017-09-06 Davide Nuzzi , Alessandro Cuccoli , Ruggero Vaia , Paola Verrucchi

We study the projection on classical spins starting from quantum equilibria. We show Gibbsianness or quasi-locality of the resulting classical spin system for a class of gapped quantum systems at low temperatures including quantum ground…

Mathematical Physics · Physics 2015-05-12 Wojciech De Roeck , Christian Maes , Karel Netočný , Marius Schütz

We use a Heisenberg spin-1/2 chain to investigate how chaos and localization may affect the entanglement of pairs of qubits. To measure how much entangled a pair is, we compute its concurrence, which is then analyzed in the…

Quantum Physics · Physics 2009-11-10 L. F. Santos , G. Rigolin , C. O. Escobar

Quantum systems can exhibit a great deal of universality at low temperature due to the structure of ground states and the critical points separating distinct states. On the other hand, quantum time evolution of the same systems involves all…

Disordered Systems and Neural Networks · Physics 2014-06-11 Ronen Vosk , Ehud Altman

We prove the existence of gapped quantum Hamiltonians whose ground states exhibit an infinite entanglement length, as opposed to their finite correlation length. Using the concept of entanglement swapping, the localizable entanglement is…

Quantum Physics · Physics 2007-05-23 F. Verstraete , M. A. Martin-Delgado , J. I. Cirac

We analyze the complexity of classically simulating continuous-time dynamics of locally interacting quantum spin systems with a constant rate of entanglement breaking noise. We prove that a polynomial time classical algorithm can be used to…

Quantum Physics · Physics 2022-11-11 Rahul Trivedi , J. Ignacio Cirac

We study the correlations of classical and quantum systems from the information theoretical points of view. We analyze a simple measure of correlations based on entropy (such measure was already investigated as the degree of entanglement by…

Quantum Physics · Physics 2012-09-13 Yuji Hirota , Dariusz Chruściński , Takashi Matsuoka , Masanori Ohya

We investigate the possibility of simulating partially entangled two qubit states by separable states of higher spins. First, we show that all partially entangled isotropic states can be simulated classically. We further investigate…

Quantum Physics · Physics 2014-01-23 H. M. Bharath , V. Ravishankar

Quantum entanglement is a central concept of quantum theory for multiple particles. Entanglement played an important role in the development of the foundations of the theory and makes possible modern applications in quantum information…

Physics Education · Physics 2015-12-09 Antje Kohnle , Erica Deffebach

Measurement-based entanglement is a method for entangling quantum systems through the state projection that accompanies a parity measurement. We derive a stochastic master equation describing measurement-based entanglement of a pair of…

Quantum Physics · Physics 2024-07-17 Remy L. Delva , Jonas Mielke , Guido Burkard , Jason R. Petta

We present a significantly improved scheme of entanglement detection inspired by local uncertainty relations for a system consisting of two qubits. Developing the underlying idea of local uncertainty relations, namely correlations, we…

Quantum Physics · Physics 2016-08-16 Christian Kothe , Gunnar Björk