Advertisement

Spin Waves in an Amorphous Heisenberg Ferromagnet

  • J. E. Gubernatis
  • P. L. Taylor

Abstract

Theoretical investigations of the ferromagnetic properties of noncrystalline solids have taken two directions - mean-field theories and Green-function calculations. The Green-function calculations1–3 have been applied only to disordered alloys or, at least, to systems in which a Bravais lattice exists; on the other hand, only mean-field theories have been applied to truly amorphous systems. As an approach to investigate the properties of an amorphous ferromagnet, the mean-field calculations4–7 have been deficient in several respects. They have not taken into proper consideration the structure of the amorphous material. Furthermore, although experiments have indicated that structural order reduces the spontaneous magnetization σ and Curie temperature Tc of the amorphous material below that of the corresponding crystalline problem, some mean-field calculations predict an increase in σ and Tc. We now present a Green-function calculation of the spectrum of an amorphous Heisenberg Ferromagnet which takes into consideration the characteristic structure of an amorphous material and which also predicts a reduction of σ and Tc.

Keywords

Lattice Site Amorphous Material Spontaneous Magnetization Perturbation Series Bravais Lattice 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    C.G. Montgomery, J.I. Krugler, and R.M. Stubbs, Phys. Rev. Letters 25, 669 (1970).ADSCrossRefGoogle Scholar
  2. 2.
    E-Ni Foo and Der-Hsuch Wu, Phys. Rev. B5, 98 (1972).Google Scholar
  3. 3.
    R. Harris and M.J. Zuckerman, Phys. Rev. B5, 101 (1972).ADSGoogle Scholar
  4. 4.
    K. Handrich, Phys. Stat. Sol.(b) 32, K55 (1969).Google Scholar
  5. 5.
    S. Kobe and K. Handrich, Phys. Stat. Sol.(b) 44, K33 (1971).Google Scholar
  6. 6.
    S. Kobe and K. Handrich, Fiz. Tverd. Tela. 13, 887 (1971) [Sov. Phys. - Solid State 13, 734 (1971)].Google Scholar
  7. 7.
    S. Kobe, Phys. Stat. Sol.(b) 41, K13 (1970).ADSCrossRefGoogle Scholar
  8. 8.
    P.L. Taylor and Shi-Yu Wu, Phys. Rev. B2 1752 (1970).Google Scholar
  9. 9.
    Details of the calculation will be published elsewhere.Google Scholar
  10. 10.
    S.V. Tyablikov, Methods in the Quantum Theory of Magnetism ( Plenum, New York, 1967 ).Google Scholar

Copyright information

© Plenum Press 1973

Authors and Affiliations

  • J. E. Gubernatis
    • 1
  • P. L. Taylor
    • 1
  1. 1.Physics DepartmentCase Western Reserve UniversityClevelandUSA

Personalised recommendations