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arXiv · 0807.3707

Origin and tuning of the magnetocaloric effect for the magnetic refrigerant MnFe(P1-xGex)

Danmin Liu·Ming Yue Jiuxing Zhang·T. M. McQueen·Jeffrey W. Lynn·Xiaolu Wang·Ying Chen·Jiying Li·R. J. Cava·Xubo Liu·Zaven Altounian·Qingzhen Huang
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Abstract

Neutron diffraction and magnetization measurements of the magneto refrigerant Mn1+yFe1-yP1-xGex reveal that the ferromagnetic and paramagnetic phases correspond to two very distinct crystal structures, with the magnetic entropy change as a function of magnetic field or temperature being directly controlled by the phase fraction of this first-order transition. By tuning the physical properties of this system we have achieved a maximum magnetic entropy change exceeding 74 J/Kg K for both increasing and decreasing field, more than twice the value of the previous record.

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Danmin Liu, Ming Yue Jiuxing Zhang, T. M. McQueen, Jeffrey W. Lynn, Xiaolu Wang, Ying Chen, Jiying Li, R. J. Cava, Xubo Liu, Zaven Altounian, Qingzhen Huang. 2009-01-27. Origin and tuning of the magnetocaloric effect for the magnetic refrigerant MnFe(P1-xGex). https://doi.org/10.1103/physrevb.79.014435

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