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arXiv · 1203.1475

Anisotropic Curie temperature materials

Jason N. Armstrong·Susan Z. Hua·Harsh Deep Chopra
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Abstract

Existence of anisotropic Curie temperature materials [E. R. Callen, Phys. Rev. 124, 1373 (1961)] is a longstanding prediction - materials that become paramagnetic along certain crystal directions at a lower temperature while remaining magnetically ordered in other directions up to a higher temperature. Validating Callen's theory, we show that all directions within the basal plane of monoclinic Fe7S8 single crystals remain ordered up to 603 K while the hard c-axis becomes paramagnetic at 225 K. Materials with such a large directional dependence of Curie temperature opens the possibility of uniquely new devices and phenomena.

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Jason N. Armstrong, Susan Z. Hua, Harsh Deep Chopra. 2012-03-07. Anisotropic Curie temperature materials. https://doi.org/10.1002/pssb.201248186

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