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Effects of Charge Ordering on Spin-Wave of Quarter-Filled Spin-Density-Wave States

Y. Tomio·Y. Kurihara·Y. Suzumura
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Abstract

Spin-wave excitations of quarter-filled spin-density-wave state, which coexists with charge ordering, have been studied for one-dimensional extended Hubbard model with the nearest-neighbor repulsive interaction (V) and next-nearest-neighbor one (V_2). We calculate dispersion relations for the acoustic and optical spin-wave within the random phase approximation. Our numerical calculation shows that energy spectrum of the acoustic branch is well described by a simple sine function form. In the states coexisting with charge-density-wave, the spin-wave velocity decreases with increasing V or V_2. Our numerical result, that velocity reduces to zero in the limit of large V or V_2, is analyzed in terms of a spin 1/2 Heisenberg model with effective antiferromagnetic exchange interaction.

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Y. Tomio, Y. Kurihara, Y. Suzumura. 2002-05-02. Effects of Charge Ordering on Spin-Wave of Quarter-Filled Spin-Density-Wave States. https://doi.org/10.1143/jpsj.71.1174

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