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arXiv · 2404.19320

Strong enhancement of magnetic coercivity induced by uniaxial stress

Bin Shen·Franziska Breitner·Philipp Gegenwart·Anton Jesche
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Abstract

The performance of permanent magnets is intricately tied to their magnetic hysteresis loop. In this study, we investigate the heavy-fermion ferromagnet CeAgSb$_2$ through magnetization measurements under uniaxial stress. We observe a 2400 % increase in magnetic coercivity with just a modest stress of approximately 1 kbar. This effect persists even after pressure release, attributable to stress-induced defects that efficiently pin domain walls. Other magnetic properties such as ordering temperature and saturation moment exhibit only weak pressure dependencies and display full reversibility. Our findings offer a promising route for increasing coercive field strength and enhancing the energy product in ferromagnetic materials and are potentially applicable to a broad spectrum of commercial or emerging magnetic applications.

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Bin Shen, Franziska Breitner, Philipp Gegenwart, Anton Jesche. 2024-04-30. Strong enhancement of magnetic coercivity induced by uniaxial stress. https://doi.org/10.1103/physrevlett.133.186702

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