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arXiv · 0906.1758

Spin-wave theory for dimerized ferromagnetic chains

Alexander Herzog·Peter Horsch·Andrzej M. Oles·Jesko Sirker
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Abstract

We describe a Peierls dimerization which occurs in ferromagnetic spin chains at finite temperature, within the modified spin-wave theory. Usual spin-wave theory is modified by introducing a Lagrange multiplier which enforces a nonmagnetic state at finite temperature. It is shown that this method gives results in excellent agreement with the density--matrix renormalization group applied to transfer matrices for dimerized ferromagnetic chains. We study bond correlation functions and explore the characteristic features of dimerization in the specific heat.

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Alexander Herzog, Peter Horsch, Andrzej M. Oles, Jesko Sirker. 2009-06-09. Spin-wave theory for dimerized ferromagnetic chains. https://doi.org/10.1088/1742-6596%2F200%2F2%2F022017

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