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arXiv · 1309.6407

Spin Gap in Heavy Fermion UBe$_{13}$

Vyacheslav G. Storchak·Jess H. Brewer·Dmitry G. Eshchenko·Patrick W. Mengyan·Oleg E. Parfenov·Pinder Dosanjh·Zachary Fisk·James L. Smith
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Abstract

Muon spin rotation ($μ^+$SR) experiments have been carried out in the heavy fermion compound UBe$_{13}$ in the temperature range from 0.025 K to 300 K and in magnetic fields up to 7 T, supported by resistivity and magnetization measurements. The $μ^+$SR spectra are characteristic of formation of a spin polaron which persists to the lowest temperature. A gap in the spin excitation spectrum of f-electrons opens up at about 180 K, consistent with anomalies discovered in resistivity, heat capacity, NMR and optical conductivity measurements of UBe$_{13}$.

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Vyacheslav G. Storchak, Jess H. Brewer, Dmitry G. Eshchenko, Patrick W. Mengyan, Oleg E. Parfenov, Pinder Dosanjh, Zachary Fisk, James L. Smith. 2013-09-25. Spin Gap in Heavy Fermion UBe$_{13}$. https://arxiv.org/abs/1309.6407

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