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arXiv · 1008.2235

Unusual signatures of the ferromagnetic transition in the heavy Fermion compound UMn$_2$Al$_{20}$

C. H. Wang·J. M. Lawrence·E. D. Bauer·K. Kothapalli·J. S. Gardner·F. Ronning·K. Gofryk·J. D. Thompson·H. Nakotte·F. Trouw
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Abstract

Magnetic susceptibility results for single crystals of the new cubic compounds UT$_2$Al$_{20}$ (T=Mn, V, and Mo) are reported. Magnetization, specific heat, resistivity, and neutron diffraction results for a single crystal and neutron diffraction and inelastic spectra for a powder sample are reported for UMn$_2$Al$_{20}$. For T = V and Mo, temperature independent Pauli paramagnetism is observed. For UMn$_2$Al$_{20}$, a ferromagnetic transition is observed in the magnetic susceptibility at $T_c$ = 20 K. The specific heat anomaly at $T_c$ is very weak while no anomaly in the resistivity is seen at $T_c$. We discuss two possible origins for this behavior of UMn$_2$Al$_{20}$: moderately small moment itinerant ferromagnetism, or induced local moment ferromagnetism.

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C. H. Wang, J. M. Lawrence, E. D. Bauer, K. Kothapalli, J. S. Gardner, F. Ronning, K. Gofryk, J. D. Thompson, H. Nakotte, F. Trouw. 2010-08-13. Unusual signatures of the ferromagnetic transition in the heavy Fermion compound UMn$_2$Al$_{20}$. https://doi.org/10.1103/physrevb.82.094406

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