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Related papers: Comb entanglement in quantum spin chains

200 papers

We describe an efficient theoretical criterion, suitable for indistinguishable particles to quantify the quantum correlations of any pure two-fermion state, based on the Slater rank concept. It represents the natural generalization of the…

Quantum Physics · Physics 2007-05-23 Fabrizio Buscemi , Paolo Bordone , Andrea Bertoni

We compute the entropy of entanglement of two blocks of L spins at a distance d in the ground state of an Ising chain in an external transverse magnetic field. We numerically study the von Neumann entropy for different values of the…

Quantum Physics · Physics 2009-01-21 P. Facchi , G. Florio , C. Invernizzi , S. Pascazio

We examine the entanglement entropy of the even half of a translationally invariant finite chain or lattice in its ground state. This entropy measures the entanglement between the even and odd halves (each forming a "comb" of $n/2$ sites)…

Quantum Physics · Physics 2011-04-26 Raul Rossignoli , Norma Canosa , Juan Mauricio Matera

The entanglement in a quantum system that possess an internal symmetry, characterized by the Sz-magnetization or U(1)-charge, is distributed among different sectors. The aim of this letter is to gain a deeper understanding of the…

Statistical Mechanics · Physics 2018-07-25 J. C. Xavier , F. C. Alcaraz , G. Sierra

Quantum entanglement is an essential resource for quantum science and technology. However, entanglement detection and quantification, via typical entanglement measures such as linear entanglement entropy or negativity, can be a very…

Quantum Physics · Physics 2025-06-17 Diego Fallas Padilla , Mingjian Zhu , Han Pu

We study solvable spin chains where either fields or couplings vary linearly in space and create a sandwich-like structure of the ground state. We find that the entanglement entropy between two halves of a chain varies logarithmically with…

Statistical Mechanics · Physics 2009-11-13 V. Eisler , F. Igloi , I. Peschel

We consider a quantum many-body system made of $N$ interacting $S{=}1/2$ spins on a lattice, and develop a formalism which allows to extract, out of conventional magnetic observables, the quantum probabilities for any selected spin pair to…

Statistical Mechanics · Physics 2007-05-23 Andrea Fubini , Tommaso Roscilde , Valerio Tognetti , Matteo Tusa , Paola Verrucchi

Quantum mechanical entanglement is a resource for quantum computation, quantum teleportation, and quantum cryptography. The ability to quantify this resource correctly has thus become of great interest to those working in the field of…

Quantum Physics · Physics 2009-11-07 J. R. Gittings , A. J. Fisher

A model of discrete dynamics of entanglement of bipartite quantum state is considered. It involves a global unitary dynamics of the system and periodic actions of local bistochastic or decaying channel. For initially pure states the decay…

Quantum Physics · Physics 2009-11-06 Karol Zyczkowski , Pawel Horodecki , Michal Horodecki , Ryszard Horodecki

The entanglement entropy of a pure quantum state of a bipartite system is defined as the von Neumann entropy of the reduced density matrix obtained by tracing over one of the two parts. Critical ground states of local Hamiltonians in one…

Strongly Correlated Electrons · Physics 2016-09-08 Eduardo Fradkin

We consider the ground state of the XX chain that is constrained to carry a current of energy. The von Neumann entropy of a block of $L$ neighboring spins, describing entanglement of the block with the rest of the chain, is computed. Recent…

Quantum Physics · Physics 2007-05-23 V. Eisler , Z. Zimboras

We provide a generalized treatment of uncertainties, von Neumann entropy, and squeezing in entangled bipartite pure state of two-level atoms. We observe that when the bipartite state is entangled, though the von Neumann entropy of the…

Quantum Physics · Physics 2025-06-04 Ram Narayan Deb

We compute the entropy of entanglement in the ground states of a general class of quantum spin-chain Hamiltonians - those that are related to quadratic forms of Fermi operators - between the first N spins and the rest of the system in the…

Quantum Physics · Physics 2009-11-10 J. P. Keating , F. Mezzadri

Electronic quantum entanglement between the central chain and the two electrodes in an infinite one-dimensional two-probe device system is studied. The entanglement entropy is calculated employing the nonequilibrium Green's function method…

Mesoscale and Nanoscale Physics · Physics 2016-03-02 Yao-Sheng Li , Wen-Long You , Xue-Feng Wang

We compute the entanglement between separated blocks in certain spin models showing that at criticality this entanglement is a function of the ratio of the separation to the length of the blocks and can be written as a product of a power…

Quantum Physics · Physics 2009-08-05 H. Wichterich , J. Molina-Vilaplana , S. Bose

The quantum entanglement $E$ of a bipartite quantum Ising chain is compared with the mutual information $I$ between the two parts after a local measurement of the classical spin configuration. As the model is conformally invariant, the…

Statistical Mechanics · Physics 2015-06-11 Jaegon Um , Hyunggyu Park , Haye Hinrichsen

We consider pure quantum states of $N\gg 1$ spins or qubits and study the average entanglement that can be \emph{localized} between two separated spins by performing local measurements on the other individual spins. We show that all…

Quantum Physics · Physics 2007-05-23 F. Verstraete , M. Popp , J. I. Cirac

Entanglement in the ground state of the XY model on the infinite chain can be measured by the von Neumann entropy of a block of neighboring spins. We study a double scaling limit: the size of the block is much larger then 1 but much smaller…

Quantum Physics · Physics 2012-01-31 F. Franchini , A. R. Its , B. -Q. Jin , V. E. Korepin

We calculate the half-chain entanglement entropy of the ground state in the one-dimensional spinless fermion model. Considering a tiny corner of the Hilbert space represented by matrix product states, we efficiently find the ground state by…

Strongly Correlated Electrons · Physics 2017-02-01 Myung-Hoon Chung

We study the entanglement between two domains of a spin-1 AKLT chain subject to open boundary conditions. In this case the ground-state manifold is four-fold degenerate. We summarize known results and present additional exact analytical…

Statistical Mechanics · Physics 2015-05-14 Scott D. Geraedts , Erik S. Sorensen