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Field induced first order antiferromagnetic to ferromagnetic transition in Al-doped CeFe$_2$: a calorimetric investigation

L. S. Sharath Chandra·Kaustav Mukherjee·V. Ganesan·A. Banerjee·P. Chaddah·M. K. Chattopadhyay·S. B. Roy
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Abstract

Field variation of heat capacity at fixed temperatures is investigated to identify the origin of the field induced first order phase transition in polycrystalline Ce(Fe$_{0.094}$Al$_{0.04}$)$_2$ sample. The heat capacity at 4.5K and 3.5K shows hysteresis in different field cycles and the virgin curve stays outside the envelope curve. This is analogous to the magnetization and magneto-resistance behavior observed in this system, where the amount of hysteresis, and the magnitude of zero-field irreversibility are attributed to the degree of supercooling/superheating, and the extent of kinetic arrest of the reverse transition from ferro- to antifrromagnetic state in field reducing cycle respectively. However, contrary to the magnetization and magneto-resistance, in heat capacity both these features have decreased with reducing temperature signifying the importance of structural contribution.

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L. S. Sharath Chandra, Kaustav Mukherjee, V. Ganesan, A. Banerjee, P. Chaddah, M. K. Chattopadhyay, S. B. Roy. 2005-08-30. Field induced first order antiferromagnetic to ferromagnetic transition in Al-doped CeFe$_2$: a calorimetric investigation. https://arxiv.org/abs/cond-mat/0508733

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