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Related papers: Quantum walk on the line: entanglement and non-loc…

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We study the behavior of bipartite entanglement at fixed von Neumann entropy. We look at the distribution of the entanglement spectrum, that is the eigenvalues of the reduced density matrix of a quantum system in a pure state. We report the…

Quantum Physics · Physics 2013-05-29 Paolo Facchi , Giuseppe Florio , Giorgio Parisi , Saverio Pascazio , Kazuya Yuasa

We investigate an asymptotically spatially flat Robertson-Walker spacetime from two different perspectives. First, using von Neumann entropy, we evaluate the entanglement generation due to the encoded information in spacetime. Then, we work…

Quantum Physics · Physics 2017-06-21 Mehrnoosh Farahmand , Hosein Mohammadzadeh , Hossein Mehri-Dehnavi

We apply a discrete quantum walk from a quantum particle on a discrete quantum spacetime from loop quantum gravity and show that the related Entanglement Entropy can drive a entropic force. We apply this concepts to propose a model of a…

High Energy Physics - Theory · Physics 2017-06-19 M. M. Amaral , R. Aschheim , Klee Irwin

We investigate how the initial and final exchange symmetries between the two-coin states influence the spatial entanglement dynamics between the two corresponding quantum walkers. Notably, when the initial state is anti-symmetric and the…

The maximum von Neumann entropy principle subject to given constraints of mean values of some physical observables determines the density matrix. Similarly the stationary action principle in the case of time-dependent (dissipative)…

Quantum Physics · Physics 2007-05-23 A. K. Rajagopal , R. W. Rendell

A recently proposed history formalism is used to define temporal entanglement in quantum systems, and compute its entropy. The procedure is based on the time-reduction of the history density operator, and allows a symmetrical treatment of…

Quantum Physics · Physics 2022-04-05 Leonardo Castellani

For a quantum state undergoing unitary Schr\"odinger time evolution, the von Neumann entropy is constant. Yet the second law of thermodynamics, and our experience, show that entropy increases with time. Ingarden introduced the quantum…

Quantum Physics · Physics 2019-07-03 Craig S. Lent

We perform the scattering analysis of the evolution operator of quantum walks with an anisotropic coin, and we prove a weak limit theorem for their asymptotic velocity. The quantum walks that we consider include one-defect models, two-phase…

Mathematical Physics · Physics 2018-06-13 S. Richard , A. Suzuki , R. Tiedra de Aldecoa

We present a bouquet of continuity bounds for quantum entropies, falling broadly into two classes: First, a tight analysis of the Alicki-Fannes continuity bounds for the conditional von Neumann entropy, reaching almost the best possible…

Quantum Physics · Physics 2016-09-06 Andreas Winter

The Von Neumann entropy of reduced states is a measure of bipartite entanglement. Despite its name, the entanglement entropy cannot by itself be used as a resource for creating thermodynamic heat flows. In order to extract heat from an…

Quantum Physics · Physics 2026-05-04 Lisa Lenstra , Jasper van Wezel

Following arXiv:2210.12963 [hep-th], we investigate aspects of the time evolution operator regarded as a density operator and associated entanglement-like structures in various quantum systems. These involve timelike separations and…

High Energy Physics - Theory · Physics 2024-04-29 K. Narayan , Hitesh K. Saini

The von Neumann entanglement entropy is a useful measure to characterize a quantum phase transition. We investigate the non-analyticity of this entropy at disorder-dominated quantum phase transitions in non-interacting electronic systems.…

Mesoscale and Nanoscale Physics · Physics 2008-01-27 X. Jia , A. R. Subramaniam , I. A. Gruzberg , S. Chakravarty

We report on the possibility of controlling quantum random walks with a step-dependent coin. The coin is characterized by a (single) rotation angle. Considering different rotation angles, one can find diverse probability distributions for…

Quantum Physics · Physics 2018-08-23 S. Panahiyan , S. Fritzsche

Quantum walks, both discrete (coined) and continuous time, form the basis of several recent quantum algorithms. Here we use numerical simulations to study the properties of discrete, coined quantum walks. We investigate the variation in the…

Quantum Physics · Physics 2008-04-21 Ivens Carneiro , Meng Loo , Xibai Xu , Mathieu Girerd , Viv Kendon , Peter L. Knight

The evolution of a many-particle system on a one-dimensional lattice, subjected to a quantum walk can cause spatial entanglement in the lattice position, which can be exploited for quantum information/communication purposes. We demonstrate…

Quantum Physics · Physics 2010-05-21 Sandeep K. Goyal , C. M. Chandrashekar

The split step quantum walk for two noninteracting particles is numerically simulated. The entropy of entanglement and spatial particle distributions are calculated for a range of initial states and for a range of disorder. The impact of…

Quantum Physics · Physics 2017-02-06 Samuel Huberman

An essential quantity in quantum information theory is the von Neumann entropy which depends entirely on the quantum density operator. Once known, the density operator reveals the statistics of observables in a quantum process, and the…

Systems and Control · Electrical Eng. & Systems 2023-09-08 Mark Balas , Vinod P. Gehlot , Tristan D. Griffith

We numerically analyze the dynamical generation of quantum entanglement in a system of 2 interacting particles, started in a coherent separable state, for decreasing values of $\hbar$. As $\hbar\to 0$ the entanglement entropy, computed at…

Quantum Physics · Physics 2015-05-30 Giulio Casati , Italo Guarneri , Jose Reslen

We follow the emergence of quantum entanglement in a scattering event between two initially uncorrelated distinguishable quantum particles interacting via a delta potential. We calculate the time dependence of the Neumann entropy of the…

Quantum Physics · Physics 2015-05-30 Mihaly G. Benedict , Judit Kovacs , Attila Czirjak

We investigate how arbitrary number of entangled qubits affects properties of quantum walk. We consider variance, positions with non-zero probability density and entropy as criteria to determine the optimal number of entangled qubits in…

Quantum Physics · Physics 2019-05-28 S. Panahiyan , S. Fritzsche