English
Related papers

Related papers: Entanglement of a Multiparticle Schroedinger Cat S…

200 papers

The entangled state that results when a detector measures a superposed quantum system has spawned decades of concern about the problem of definite outcomes or "Schrodinger's cat." This state seems to describe a detector in an indefinite or…

Quantum Physics · Physics 2022-06-14 Art Hobson

Two electronic channels competing to screen a single impurity spin, as in the two-channel Kondo model, are expected to generate a ground state with nontrivial entanglement structure. We exploit a spin-chain representation of the two-channel…

A qubit (a spin-1/2 particle) prepared in the up state is scattered by local spin-flipping potentials produced by the two target qubits (two fixed spins), both prepared in the down state, to generate an entangled state in the latter when…

Quantum Physics · Physics 2009-07-11 Yuichiro Hida , Hiromichi Nakazato , Kazuya Yuasa , Yasser Omar

The Mermin inequality provides a criterion for experimentally ruling out local-realistic descriptions of multiparticle systems. A violation of this inequality means that the particles must be entangled, but does not, in general, indicate…

Quantum Physics · Physics 2011-02-25 Mark S. Everitt , Martin L. Jones , Benjamin T. H. Varcoe , Jacob A. Dunningham

We study the dynamical process of disentanglement of two qubits and two qutrits coupled to an Ising spin chain in a transverse field, which exhibits a quantum phase transition. We use the concurrence and negativity to quantify entanglement…

Quantum Physics · Physics 2009-11-13 Zhe Sun , Xiaoguang Wang , C. P. Sun

A key requirement of any separable quantum state is that its density matrix has a positive partial transpose. For continuous bipartite quantum states, violation of this condition may be tested via the hierarchy of negative-partial-transpose…

Quantum Physics · Physics 2025-02-28 Lydia A. Kanari-Naish , Jack Clarke , Sofia Qvarfort , Michael R. Vanner

Entanglement within qubits are studied for the subspace of definite particle states or definite number of up spins. A transition from an algebraic decay of entanglement within two qubits with the total number $N$ of qubits, to an…

Quantum Physics · Physics 2012-02-20 Vikram S Vijayaraghavan , Udaysinh T. Bhosale , Arul Lakshminarayan

We identify a general criterion for detecting entanglement of pure bipartite quantum states describing a system of two identical particles. Such a criterion is based both on the consideration of the Slater-Schmidt number of the fermionic…

Quantum Physics · Physics 2016-09-08 GianCarlo Ghirardi , Luca Marinatto

We present a theoretical method to determine the multipartite entanglement between different partitions of multimode, fully or partially symmetric Gaussian states of continuous variable systems. For such states, we determine the exact…

Quantum Physics · Physics 2007-05-23 Gerardo Adesso , Alessio Serafini , Fabrizio Illuminati

Quantum entanglement of pure states of a bipartite system is defined as the amount of local or marginal ({\em i.e.}referring to the subsystems) entropy. For mixed states this identification vanishes, since the global loss of information…

Quantum Physics · Physics 2007-05-23 Gerardo Adesso , Alessio Serafini , Fabrizio Illuminati

We study the entanglement creation in the low-energy scattering of two particles in three dimensions, for a general class of interaction potentials that are not required to be spherically symmetric. The incoming asymptotic state, before the…

Quantum Physics · Physics 2012-01-06 Ricardo Weder

A characterization of N-partite states, based on K-way (K = 2 to N) negativities, is proposed. The K-way partial transpose with respect to a subsystem is defined so as to shift the focus to K-way coherences instead of K subsystems of the…

Quantum Physics · Physics 2008-07-07 S. Shelly Sharma , N. K. Sharma

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

Consider a system consisting of $n$ $d$-dimensional quantum particles and arbitrary pure state $\Psi$ of the whole system. Suppose we simultaneously perform complete von Neumann measurements on each particle. One can ask: what is the…

Quantum Physics · Physics 2009-11-07 Sergei Bravyi

We propose entanglement negativity as a fine-grained probe of measurement-induced criticality. We motivate this proposal in stabilizer states, where for two disjoint subregions, comparing their "mutual negativity" and their mutual…

Statistical Mechanics · Physics 2021-07-28 Shengqi Sang , Yaodong Li , Tianci Zhou , Xiao Chen , Timothy H. Hsieh , Matthew P. A. Fisher

We exhibit a two-parameter class of states $\rho_{(\alpha,\gamma)}$, in $2\otimes n$ quantum system for $n\ge 3$, which can be obtained from an arbitrary state by means of local quantum operations and classical communication, and which are…

Quantum Physics · Physics 2009-11-10 Dong Pyo Chi , Soojoon Lee

We summarize a recently proposed resolution of the quantum measurement problem. It stems from an insight into entanglement demonstrated in a 1991 experiment involving photon momenta. This experiment shows that, when two superposed quantum…

Quantum Physics · Physics 2025-06-24 Art Hobson

Schr\"odinger's cat originates from the famous thought experiment querying the counterintuitive quantum superposition of macroscopic objects. As a natural extension, several "cats" (quasi-classical objects) can be prepared into coherent…

The von Neumann entropy of a $k$-body reduced density matrix $\gamma_k$ quantifies the entanglement between $k$ quantum particles and the remaining ones. In this short paper, we rigorously prove general properties of this entanglement…

Quantum Physics · Physics 2024-12-17 Marius Lemm

Quantification of entanglement is one of the most important problem in quantum information theory. In this work, we will study this problem by defining a physically realizable measure of entanglement for any arbitrary dimensional bipartite…

Quantum Physics · Physics 2023-05-02 Anu Kumari , Satyabrata Adhikari