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Observation of an unusual equilibrium in the molecular nano-magnet Fe_8

V. Villar·E. Lhotel·C. Sangregorio·C. Paulsen
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Abstract

Magnetization measurements made in small fields as a function of temperature reveal an unusual equilibrium below 900 mK for the molecular nano-magnet Fe_8. Measurements of the relaxation of the magnetization demonstrate that the approach to the equilibrium is non-trivial and suggest that a competition exists between quantum tunneling of the giant spins and thermodynamic behavior. As a result, at very low temperature the entropy of the spin system remains very large.

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V. Villar, E. Lhotel, C. Sangregorio, C. Paulsen. 2005-08-05. Observation of an unusual equilibrium in the molecular nano-magnet Fe_8. https://arxiv.org/abs/cond-mat/0508157

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