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Magnetic Field Effects on Neutron Diffraction in the Antiferromagnetic Phase of $UPt_3$

Juana Moreno·J. A. Sauls
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Abstract

We discuss possible magnetic structures in UPt$_3$ based on our analysis of elastic neutron-scattering experiments in high magnetic fields at temperatures $T<T_N$. The existing experimental data can be explained by a single-{\bf q} antiferromagnetic structure with three independent domains. For modest in-plane spin-orbit interactions, the Zeeman coupling between the antiferromagnetic order parameter and the magnetic field induces a rotation of the magnetic moments, but not an adjustment of the propagation vector of the magnetic order. A triple-{\bf q} magnetic structure is also consistent with neutron experiments, but in general leads to a non-uniform magnetization in the crystal. New experiments could decide between these structures.

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Juana Moreno, J. A. Sauls. 2000-04-14. Magnetic Field Effects on Neutron Diffraction in the Antiferromagnetic Phase of $UPt_3$. https://doi.org/10.1103/physrevb.63.024419

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