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arXiv · 2201.11401

Thermodynamics of the classical spin triangle

Heinz-Jürgen Schmidt·Christian Schröder
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Abstract

The classical spin system consisting of three spins with Heisenberg interaction is an example of a completely integrable mechanical system. In this paper we explicitly calculate thermodynamic quantities as density of states, specific heat, susceptibility and spin autocorrelation functions. These calculations are performed (semi-)analytically and shown to agree with corresponding Monte Carlo simulations. For the long-time autocorrelation function, we find, for certain values of the coupling constants, a decay to constant values in the form of an $1/t$ damped harmonic oscillation and propose a theoretical explanation.

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Heinz-Jürgen Schmidt, Christian Schröder. 2022-01-27. Thermodynamics of the classical spin triangle. https://doi.org/10.1515/zna-2022-0034

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