Advertisement

Double exchange model for nanoscopic clusters

  • David Rotter
  • Angelo Valli
  • Giorgio Sangiovanni
  • Karsten Held
Regular Article

Abstract

We solve the double exchange model on nanoscopic clusters exactly, and specifically consider a six-site benzene-like nanocluster. This simple model is an ideal testbed for studying magnetism in nanoclusters and for validating approximations such as the dynamical mean field theory (DMFT). Non-local correlations arise between neighboring localized spins due to the Hund’s rule coupling, favoring a short-range magnetic order of ferro or antiferromagnetic type. For a geometry with more neighboring sites or a sufficiently strong hybridization between leads and the nanocluster, these non-local correlations are less relevant, and DMFT can be applied reliably.

Keywords

Mesoscopic and Nanoscale Systems 

References

  1. 1.
    R. von Helmolt, J. Wecker, B. Holzapfel, L. Schultz, K. Samwer, Phys. Rev. Lett. 71, 2331 (1993) ADSCrossRefGoogle Scholar
  2. 2.
    K. Chahara, T. Ohno, M. Kasai, Y. Kozono, Appl. Phys. Lett. 63, 1990 (1993) ADSCrossRefGoogle Scholar
  3. 3.
    S. Jin, T.H. Tiefel, M. McCormack, R.A. Fastnacht, R. Ramesh, L.H. Chen, Science 264, 413 (1994) ADSCrossRefGoogle Scholar
  4. 4.
    P. Schiffer, A.P. Ramirez, W. Bao, S.-W. Cheong, Phys. Rev. Lett. 75, 3336 (1995) ADSCrossRefGoogle Scholar
  5. 5.
    C. Zener, Phys. Rev. 82, 403 (1951)ADSCrossRefGoogle Scholar
  6. 6.
    T. Sarkar, A.K. Raychaudhuri, T. Chatterji, Appl. Phys. Lett. 92, 123104 (2008) ADSCrossRefGoogle Scholar
  7. 7.
    T. Sarkar, A.K. Raychaudhuri, T. Chatterji, J. Appl. Phys. 101, 124307 (2007) ADSCrossRefGoogle Scholar
  8. 8.
    S.S. Rao et al., Appl. Phys. Lett. 87, 182503 (2005) ADSCrossRefGoogle Scholar
  9. 9.
    H. Das, G. Sangiovanni, A. Valli, K. Held, T. Saha-Dasgupta, Phys. Rev. Lett. 107, 197202 (2011) ADSCrossRefGoogle Scholar
  10. 10.
    A. Valli, G. Sangiovanni, O. Gunnarsson, A. Toschi, K. Held, Phys. Rev. Lett. 104, 246402 (2010) ADSCrossRefGoogle Scholar
  11. 11.
    A. Valli, G. Sangiovanni, A. Toschi, K. Held, Phys. Rev. B 86, 115418 (2012) ADSCrossRefGoogle Scholar
  12. 12.
    W. Metzner, D. Vollhardt, Phys. Rev. Lett. 62, 324 (1989)ADSCrossRefGoogle Scholar
  13. 13.
    A. Georges, G. Kotliar, Phys. Rev. B 45, 6479 (1992) ADSCrossRefGoogle Scholar
  14. 14.
    A. Georges, G. Kotliar, W. Krauth, M. Rozenberg, Rev. Mod. Phys. 68, 13 (1996)MathSciNetADSCrossRefGoogle Scholar
  15. 15.
    N. Furukawa, J. Phys. Soc. Jpn 63, 3214 (1994) ADSCrossRefGoogle Scholar
  16. 16.
    N. Furukawa, in Physics of Manganites, edited by T.A. Kaplan, S.D. Mahanti (Kluwer, New York, 1999) Google Scholar
  17. 17.
    W. Negele, H. Orland, Quantum Many-Particle Systems (Addison-Wesley, New York, 1987)Google Scholar
  18. 18.
    S. Florens, Phys. Rev. Lett. 99, 046402 (2007) ADSCrossRefGoogle Scholar
  19. 19.
    M. Potthoff, W. Nolting, Phys. Rev. B 59, 2549 (1999) ADSCrossRefGoogle Scholar
  20. 20.
    M. Snoek, I. Titvinidze, C. Tőke, K. Byczuk, W. Hofstetter, New J. Phys. 10, 093008 (2008) ADSCrossRefGoogle Scholar
  21. 21.
    A. Toschi, A.A. Katanin, K. Held, Phys. Rev. B 75, 045118 (2007) ADSCrossRefGoogle Scholar
  22. 22.
    K. Held, A.A. Katanin, A. Toschi, Prog. Theor. Phys. Suppl. 176, 117 (2008) CrossRefGoogle Scholar
  23. 23.
    A.A. Katanin, A. Toschi, K. Held, Phys. Rev. B 80, 075104 (2009) ADSCrossRefGoogle Scholar
  24. 24.
    G. Rohringer, A. Toschi, A.A. Katanin, K. Held, Phys. Rev. Lett. 107, 256402 (2011) ADSCrossRefGoogle Scholar
  25. 25.
    S. Henning, P. Herrmann, W. Nolting, Phys. Rev. B 86, 085101 (2012) ADSCrossRefGoogle Scholar
  26. 26.
    T. Maier, M. Jarrell, T. Pruschke, M.H. Hettler, Rev. Mod. Phys. 77, 1027 (2005) ADSCrossRefGoogle Scholar
  27. 27.
    H. Kusunose, J. Phys. Soc. Jpn 75, 054713 (2006) ADSCrossRefGoogle Scholar
  28. 28.
    C. Slezak, M. Jarrell, T. Maier, J. Deisz, J. Phys.: Condens. Matter 21, 435604 (2009) ADSCrossRefGoogle Scholar
  29. 29.
    G. Rohringer, A. Valli, A. Toschi, Phys. Rev. B 86, 125114 (2012) ADSCrossRefGoogle Scholar

Copyright information

© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • David Rotter
    • 1
  • Angelo Valli
    • 1
  • Giorgio Sangiovanni
    • 1
    • 2
  • Karsten Held
    • 1
  1. 1.Institute of Solid State PhysicsVienna University of TechnologyViennaAustria
  2. 2.Institute for Theoretical Physics and AstrophysicsUniversity of WürzburgWürzburgGermany

Personalised recommendations