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Prog. Theor. Phys. Vol. 97 No. 1 (1997) pp. 21-47

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Spin Wave and Stability of the Double Exchange Ferromagnet

Takuya Okabe

Department of Physics, Kyoto University, Kyoto 606-01

(Received September 5, 1996)

Abstract:

To investigate the spin wave and the stability of the ferromagnetic Kondo lattice, we describe the state with Sz = S - 1 and that with Sz = S - 1/2 in terms of the variational wave function. In this model, it is found that the spin-wave spectrum does not differ appreciably from the RPA result, since the bottom of the individual-particle excitation lies in a relatively high energy region. In this article, the double exchange ferromagnet is discussed with the Nagaoka ferromagnetic state of the U = ∞ Hubbard model, with respect to the stability of the ferromagnetic state.


URL : http://ptp.ipap.jp/link?PTP/97/21/
DOI : 10.1143/PTP.97.21

[ Full Text PDF : FREE ACCESS (1321K) ] Citation:

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References:

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Citing Article(s) :

  1. Journal of the Physical Society of Japan 68 (1999) pp. 1008-1010 :
    The Curie Temperature of the Double-Exchange Interaction Systems
    Chong Der Hu
  2. Journal of the Physical Society of Japan 68 (1999) pp. 3682-3692 :
    Electron Correlations in the Nagaoka State on the Square Lattice -Three-Body Correlations-
    Jun-ichi Igarashi, Manabu Takahashi and Tatsuya Nagao
  3. Journal of the Physical Society of Japan 69 (2000) pp. 1837-1844 :
    Magnetic Order in the Double Exchange Model in Infinite Dimensions
    Kentaro Nagai, Tsutomu Momoi and Kenn Kubo
  4. Journal of the Physical Society of Japan 69 (2000) pp. 3704-3710 :
    The Magnetization and Curie Temperature of the Double Exchange Interaction Systems
    Chong Der Hu
  5. Progress of Theoretical Physics Vol. 98 No. 2 (1997) pp. 331-349 :
    Hund's-Rule Coupling Effect in Itinerant Ferromagnetism
    Takuya Okabe

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