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arXiv · 1709.05007

Imaging the magnetic states in an actinide ferromagnet UMn$_2$Ge$_2$

Xinzhou Tan·Morgann Berg·Jeehoon Kim·Ryan E. Baumbach·Eric D. Bauer·Joe D. Thompson·Filip Ronning·Alex de Lozanne
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Abstract

We present studies of the magnetic domain structure of UMn$_2$Ge$_2$ single crystals using a home-built low temperature magnetic force microscope. The material has two distinct magnetic ordering temperatures, originating from the Mn and U moments. At room temperature, where the Mn moments dominate, there are flower-like domain patterns similar to those observed in uniaxial ferromagnets. After exposing the sample to a one-tesla magnetic field near 40 K, the evolution of the magnetic domains are imaged through zero-field warming up to 200 K. Near the ordering temperature of the uranium moments a clear change in the domain wall motion is observed. The domain size analysis of the flower-like pattern reveals that the domain structure is consistent with a model of branching domains.

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Xinzhou Tan, Morgann Berg, Jeehoon Kim, Ryan E. Baumbach, Eric D. Bauer, Joe D. Thompson, Filip Ronning, Alex de Lozanne. 2017-09-14. Imaging the magnetic states in an actinide ferromagnet UMn$_2$Ge$_2$. https://doi.org/10.1103/physrevmaterials.2.074402

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