Abstract
After a brief introduction to the concept of entanglement in quantum systems, I apply these ideas to many-body systems and show that the von Neumann entropy is an effective way of characterising the entanglement between the degrees of freedom in different regions of space. Close to a quantum phase transition it has universal features which serve as a diagnostic of such phenomena. In the second part I consider the unitary time evolution of such systems following a ‘quantum quench’ in which a parameter in the Hamiltonian is suddenly changed, and argue that finite regions should effectively thermalise at late times, after interesting transient effects.
Similar content being viewed by others
References
P. Calabrese, J. Cardy, J. Stat. Mech. 0406, P06002 (2004)
P. Calabrese, J. Cardy, J. Stat. Mech. 0504, P04010 (2005)
P. Calabrese, J. Cardy, Phys. Rev. Lett. 96, 136801 (2006); P. Calabrese, J. Cardy, J. Stat. Mech. 0706, P008 (2007)
L. Amico, R. Fazio, A. Osterloh, V. Vedral, to appear in Rev. Mod. Phys.; e-print arXiv:quant-ph/0703044
C.H. Bennett, H.J. Bernstein, S. Popescu, B. Schumacher, Phys. Rev. A 53, 2046 (1996)
C. Holzhey, F. Larsen, F. Wilczek, Nucl. Phys. B 424, 44 (1994)
G. Refael, J.E. Moore, Phys. Rev. Lett. 93, 260602 (2001)
V. Korepin, Phys. Rev. Lett. 92, 096402 (2004)
I. Peschel, J. Stat. Mech. 0412, P12005 (2004)
J. Cardy, O. Castro-Alvaredo, B. Doyon, to appear in J. Stat. Phys., e-print arXiv:0706.3384
M.M. Wolf, F. Verstraete, M.B. Hastings, J.I. Cirac, e-print arXiv:0704.3906
E. Barouch, B. McCoy, Phys. Rev. A 2, 1075 (1970); E. Barouch, B. McCoy, Phys. Rev. A 3, 786 (1971); E. Barouch, B. McCoy, Phys. Rev. A 3, 2137 (1971)
K. Sengupta, S. Powell, S. Sachdev, Phys. Rev. A 69, 053616 (2004)
V. Eisler, I. Peschel, J. Stat. Mech. 0706, P06005 (2007)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Cardya, J.L. Entanglement entropy in extended quantum systems. Eur. Phys. J. B 64, 321–326 (2008). https://doi.org/10.1140/epjb/e2008-00102-5
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1140/epjb/e2008-00102-5