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Title: Superballistic diffusion of entanglement in disordered spin chains

Abstract

We study the dynamics of a single excitation in an infinite XXZ spin chain, which is launched from the origin. We study the time evolution of the spread of entanglement in the spin chain and obtain an expression for the second-order spatial moment of concurrence, about the origin, for both ordered and disordered chains. In this way, we show that a finite central disordered region can lead to sustained superballistic growth in the second-order spatial moment of entanglement within the chain.

Authors:
 [1];  [1];  [2]
  1. Department of Mathematical Physics, National University of Ireland, Maynooth, County Kildare (Ireland)
  2. (Australia)
Publication Date:
OSTI Identifier:
20786415
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.72.050301; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 36 MATERIALS SCIENCE; DIFFUSION; EXCITATION; INFORMATION THEORY; QUANTUM ENTANGLEMENT; QUANTUM MECHANICS; SPIN

Citation Formats

Fitzsimons, J., Twamley, J., and Centre for Quantum Computer Technology, Macquarie University, Sydney, New South Wales 2109. Superballistic diffusion of entanglement in disordered spin chains. United States: N. p., 2005. Web. doi:10.1103/PHYSREVA.72.0.
Fitzsimons, J., Twamley, J., & Centre for Quantum Computer Technology, Macquarie University, Sydney, New South Wales 2109. Superballistic diffusion of entanglement in disordered spin chains. United States. doi:10.1103/PHYSREVA.72.0.
Fitzsimons, J., Twamley, J., and Centre for Quantum Computer Technology, Macquarie University, Sydney, New South Wales 2109. Tue . "Superballistic diffusion of entanglement in disordered spin chains". United States. doi:10.1103/PHYSREVA.72.0.
@article{osti_20786415,
title = {Superballistic diffusion of entanglement in disordered spin chains},
author = {Fitzsimons, J. and Twamley, J. and Centre for Quantum Computer Technology, Macquarie University, Sydney, New South Wales 2109},
abstractNote = {We study the dynamics of a single excitation in an infinite XXZ spin chain, which is launched from the origin. We study the time evolution of the spread of entanglement in the spin chain and obtain an expression for the second-order spatial moment of concurrence, about the origin, for both ordered and disordered chains. In this way, we show that a finite central disordered region can lead to sustained superballistic growth in the second-order spatial moment of entanglement within the chain.},
doi = {10.1103/PHYSREVA.72.0},
journal = {Physical Review. A},
number = 5,
volume = 72,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
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