期刊文献+

Ferromagnetism in an Itinerant Electron Cluster 被引量:1

下载PDF
导出
摘要 In the present paper, we study the existence of metallic ferromagnetism in a cluster of nanometer scale,which is described by the Hubbard model defined on a complete graph. Therefore, the system is highly frustrated with respect to electron hopping. By solving the model exactly, we show that its ground state is fully spin-polarized at half-filling, even if the Coulomb interaction is finite. This conclusion is in sharp contrast to the well-known result for the Hubbard model on a bipartite lattice. As a result, our exact solution strongly suggests that frustration may play an important role in causing metallic ferromagnetism.
机构地区 SchoolofPhysics
出处 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1X期188-192,共5页 理论物理通讯(英文版)
基金 国家自然科学基金
  • 引文网络
  • 相关文献

参考文献16

  • 1D.C. Mattis, The Theory of Magnetism I, Springer-Verlag, Berlin (1981).
  • 2J. Hubbard, Proc. Roy. Soc. London A 276 (1963) 238.
  • 3C. Herring, Magnetism IV, eds. G.T. Rado and H. Suhl,Academic, New York (1966).
  • 4J. Kanamori, Prog. Theor. Phys. 30 (1963) 275.
  • 5Y. Nagaoka, Phys. Rev. 147 (1966) 392.
  • 6G.S. Tian, J. Phys. A: Math. Gen. 23 (1990) 2231.
  • 7G.S. Tian, Phys. Rev. B 44 (1991) 4444.
  • 8E.H. Lieb, Phys. Rev. Lett. 62 (1989) 1201.
  • 9A. Mielke, J. Phys. A: Math. Gen. 24 (1991) L73; ibid.24 (1991) 3311.
  • 10H. Tasaki, Phys. Rev. Lett. 69 (1992) 1608.

同被引文献13

  • 1HUBBARD J. Electron correlations in narrow energy bands [J]. Proceedings of the Royal Society of London A, 1963, 276:238-257.
  • 2ANDERSON P W. New approach to the theory of super -exchange interactions [ J ]. Physical Review, 1959,115:2-13.
  • 3SPALEK J, OLES A M, CHAO K A. Magnetic phases of strongly correlated electrons in a nearly half-filled narrow band [J]. Physica Status Solidi ( b), 1981,108(2) :329- 340.
  • 4NAGAOKA Y. Ferromagnetism in a narrow, almost half - filled s band [ J ]. Physical Review, 1966,147:392-405.
  • 5MULLER-HARTMANN E. Ferromagnetism in Hubbard models-low density route [ J]. Journal of Low Temperature physics, 1995, 99: 349-354.
  • 6WANG D F. Ferromagnetism in an itinerant electron system: Hubbard model on complete graph [ J]. cond-mat/ 9604121,1996.
  • 7FARKASOVSKY P. Ferromagnetism in the Hubbard model with a generalized type of hopping [ J ]. Phys Rev B 66, 2002,012404.
  • 8HORI H, YAMAMOTO Y, IWAMOTO T, et al. Diameter dependence of ferromagnetic spin moment in Au nanocrystals [J]. Phys Rev B 69, 2004,174411.
  • 9SAMPEDRO B, CRESPO P, HERNANDO A, et al. Ferromagnetism in fcc twinned 2.4nm size Pd nanoparticles [J]. Phys Rev Lett 91, 2003,237203.
  • 10CRESPO P, LITRAN R, ROJAS T C, et al. Permanent magnetism, magnetic anisotropy, and hysteresis of ThiolCapped gold nanoparticles [ J ]. Phys Rev Lett 93, 2004, 087204.

引证文献1

;
使用帮助 返回顶部