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On the Motion of Vortex Pairs in the Anisotropic Heisenberg Model

  • A. R. Völkel
  • F. G. Mertens
  • A. R. Bishop
  • G. M. Wysin
Part of the NATO ASI Series book series (NSSB, volume 264)

Abstract

We consider a classical 2D Heisenberg model with easy-plane symmetry. Koster-litz and Thouless1 showed that such a system has a topological phase transition: at low temperatures there exist bound vortex pairs which start to dissociate above a critical temperature T KT Just above T KT we can assume that there are only a few free vortices which move ballistically between their interactions. A model of dynamics built on such a “vortex gas” has been constructed assuming a Gaussian velocity distribution. Here we use effective equations of motion for the collective (center-of-mass) vortex variables and compare these analytical results of vortex-vortex and vortex-anitvortex interactions with molecular dynamics simulations of the full spin system.3 We investigate both ferromagnets (FM) and antiferromagnets (AFM) with an anisotropy parameter λ varying from zero to one.

Keywords

Static Force Anisotropy Parameter Elsevier Science Publisher Vortex Pair Heisenberg Model 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    J. M. Kosterlitz, D. J. Thouless, J. Phys. C6 1181 (1973)ADSGoogle Scholar
  2. 1a.
    J. M. Kosterlitz, J. Phys. C7 1046 (1974).ADSGoogle Scholar
  3. 2.
    F. G. Mertens, A. R. Bishop, G. M. Wysin, C. Kawabata, Phys. Rev. B39 591 (1989)ADSGoogle Scholar
  4. 2a.
    M. E. Gouvêa, G. M. Wysin, A. R. Bishop, F. G. Mertens, Phys. Rev. B39 11840 (1989).ADSGoogle Scholar
  5. 3.
    A. R. Völkel, F. G. Mertens, A. R. Bishop, G. M. Wysin, Phys. Rev. B, in press.Google Scholar
  6. 4.
    A. A. Belavin, A. M. Polyakov, Pis’ma Zh. Eksp. Teor. Fiz. 22 503 (1975)Google Scholar
  7. 4.
    A. A. Belavin, A. M. Polyakov Jet Lett. 22 245 (1975).ADSGoogle Scholar
  8. 5.
    A. A. Thiele, Phys. Rev. Lett. 30 230 (1973)ADSCrossRefGoogle Scholar
  9. 5a5b.
    D. L. Huber, Phys. Rev. B26 3758 (1982) V. L. Pokrovsky, M. V. Feigl’man, A. M. Tsvelick, in “Spin Waves and Magnetic Excitations,” ed. A. S. Borovik-Romanov, S. K. Sinha (Elsevier Science Publishers B. V.), Chapter II (1988).ADSGoogle Scholar
  10. 6.
    J. Friedel, “Dislocations,” Oxford, New York, Pergamon Press (1964).MATHGoogle Scholar
  11. 7.
    H. M. Wu, E. A. Overman II, N. J. Zabusky, J. Comp. Phys. 53 42 (1984).MathSciNetADSMATHCrossRefGoogle Scholar
  12. 8.
    I. Halperin, D. R. Nelson, J. Low. Temp. Phys. 36 599 (1979).ADSCrossRefGoogle Scholar
  13. 9.
    W. J. Glaberson, R. J. Donnelly, Prog. Low Temp. Phys., Vol. IX, ed. D. F. Brewer (Elsevier Science Publishers B. V., 1986).Google Scholar

Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • A. R. Völkel
    • 1
  • F. G. Mertens
    • 1
  • A. R. Bishop
    • 1
  • G. M. Wysin
    • 1
  1. 1.Theoretical Division and CNLSLANLLos AlamosUSA

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