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arXiv · 1206.2540

History dependence of directly observed magnetocaloric effects in (Mn, Fe)As

Milan Bratko·Kelly Morrison·Ariana de Campos·Sergio Gama·Lesley F. Cohen·Karl G. Sandeman
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Abstract

We use a calorimetric technique operating in sweeping magnetic field to study the thermomagnetic history- dependence of the magnetocaloric effect (MCE) in Mn0.985Fe0.015As. We study the magnetization history for which a "colossal" MCE has been reported when inferred indirectly via a Maxwell relation. We observe no colossal effect in the direct calorimetric measurement. We further examine the impact of mixed-phase state on the MCE and show that the first order contribution scales linearly with the phase fraction. This validates various phase-fraction based methods developed to remove the colossal peak anomaly from Maxwell-based estimates.

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Milan Bratko, Kelly Morrison, Ariana de Campos, Sergio Gama, Lesley F. Cohen, Karl G. Sandeman. 2012-06-12. History dependence of directly observed magnetocaloric effects in (Mn, Fe)As. https://doi.org/10.1063/1.4729893

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