Spin-wave softening and Hund's coupling in ferromagnetic manganites

Abstract

Using one-orbital model of hole-doped manganites, we show with the help of Holstein-Primakov transformation that finite Hund's coupling is responsible for the spin-wave softening in the ferromagnetic $B$-phase manganites. We obtain an analytical result for the spin-wave spectrum for $\JH\gg t$. In the limit of infinte Hund's coupling, the spectrum is the conventional nearest-neighbor Heisenberg ferromagnetic spin-wave. The $o(t/\JH)$-order correction is negative and thus accounts for the softening near the zone boundary.

arXiv comment5 pages, 3 figures

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Cited by in corpus (3)

• Magnons in Ferromagnetic Metallic Manganites
• Three--body Correlation Effects on the Spin Dynamics of Double--Exchange Ferromagnets
• Spin, orbital and topological order in models of strongly correlated electrons