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Thermodynamics of finite magnetic two-level systems

Peter Borrmann·Heinrich Stamerjohanns·Eberhard Hilf·Philippe Jund·Seon Gon Kim·David Tomanek
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Abstract

We use Monte Carlo simulations to investigate the thermodynamical behaviour of aggregates consisting of few superparamagnetic particles in a colloidal suspension. The potential energy surface of this classical two-level system with a stable and a metastable `ring' and `chain' configuration is tunable by an external magnetic field and temperature. We determine the complex `phase diagram' of this intriguing system and analyze thermodynamically the nature of the transition between the ring and the chain `phase'.

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Peter Borrmann, Heinrich Stamerjohanns, Eberhard Hilf, Philippe Jund, Seon Gon Kim, David Tomanek. 1996-01-29. Thermodynamics of finite magnetic two-level systems. https://arxiv.org/abs/cond-mat/9601138

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