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

Sze-Shiang Feng·Mogus Mochena
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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.

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Sze-Shiang Feng, Mogus Mochena. 2005-06-14. Spin-wave softening and Hund's coupling in ferromagnetic manganites. https://doi.org/10.1088/0953-8984%2F17%2F25%2F016

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