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Effect of nearest- and next-nearest neighbor interactions on the spin-wave velocity of one-dimensional quarter-filled spin-density-wave conductors

Y. Tomio·N. Dupuis·Y. Suzumura
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Abstract

We study spin fluctuations in quarter-filled one-dimensional spin-density-wave systems in presence of short-range Coulomb interactions. By applying a path integral method, the spin-wave velocity is calculated as a function of on-site (U), nearest (V) and next-nearest (V_2) neighbor-site interactions. With increasing V or V_2, the pure spin-density-wave state evolves into a state with coexisting spin- and charge-density waves. The spin-wave velocity is reduced when several density waves coexist in the ground state, and may even vanish at large V. The effect of dimerization along the chain is also considered.

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Y. Tomio, N. Dupuis, Y. Suzumura. 2001-10-04. Effect of nearest- and next-nearest neighbor interactions on the spin-wave velocity of one-dimensional quarter-filled spin-density-wave conductors. https://doi.org/10.1103/physrevb.64.125123

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