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Spin wave analysis of Heisenberg magnets in restricted geometries

N. B. Ivanov·D. Sen
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Abstract

In the last decade it has been proven that the standard spin wave theory was able to provide accurate zero-temperature results for a number of low-dimensional Heisenberg spin systems. In this chapter we introduce the main ingredients of the spin-wave technique using as a working model the two-leg mixed-spin ferrimagnetic ladder and the Dyson--Maleev boson formalism up to second order in the spin-wave interaction. In the remainder, we survey typical applications in low-space dimensionality as well as some recent modifications of the theory admitting a quantitative analysis in magnetically disordered phases. The presented spin-wave results are compared with available numerical estimates.

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N. B. Ivanov, D. Sen. 2004-12-29. Spin wave analysis of Heisenberg magnets in restricted geometries. https://doi.org/10.1007/bfb0119594

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