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Quantum Spin Effect and Short-Range Order above the Curie Temperature

R. Y. Gu·V. P. Antropov
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Abstract

Using quantum Heisenberg model calculations with Green's function technique generalized for arbitrary spins, we found that for a system of small spins the quantum spin effects significantly contribute to the magnetic short-range order and strongly affect physical properties of magnets. The spin dynamics investigation confirms that these quantum spin effects favor the persistence of propagating spin-wave excitations above the Curie temperature. Our investigation suggests a reconsideration of prevailing point of view on finite temperature magnetism to include quantum effects and the magnetic short-range order.

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R. Y. Gu, V. P. Antropov. 2005-08-31. Quantum Spin Effect and Short-Range Order above the Curie Temperature. https://arxiv.org/abs/cond-mat/0508781

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