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arXiv · 2604.11242

Magnetic Order of Dresselhaus-type Antiferromagnet EuIr$_4$In$_2$Ge$_4$ Studied by Single Crystal Neutron Diffraction

Chihiro Tabata·Koji Kaneko·Akiko Nakao·Takashi Ohhara·Tatsuma D. Matsuda·Yoshichika Ōnuki
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Abstract

The magnetic order of EuIr$_4$In$_2$Ge$_4$, which crystallizes in a Dresselhaus-type noncentrosymmetric tetragonal structure, was investigated using two complementary single-crystal neutron diffraction approaches. Time-of-flight single-crystal diffraction reveals antiferromagnetic Bragg reflections with propagation vector $q = (1, 0, 0)$ below the N\'{e}el temperature $T_{\rm N}$ = 2.5 K, indicating a breaking of body-centered translational symmetry. Polarized neutron diffraction on a triple-axis spectrometer demonstrates that the ordered Eu$^{2+}$ $4f$ moments lie within the basal plane and form a collinear antiferromagnetic structure with antiparallel alignment between corner and body-center sites. Despite the Dresselhaus-type spin splitting in the conduction bands, the magnetic order remains simple, implying weak coupling between localized moments and itinerant electrons.

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Chihiro Tabata, Koji Kaneko, Akiko Nakao, Takashi Ohhara, Tatsuma D. Matsuda, Yoshichika Ōnuki. 2026-04-13. Magnetic Order of Dresselhaus-type Antiferromagnet EuIr$_4$In$_2$Ge$_4$ Studied by Single Crystal Neutron Diffraction. https://doi.org/10.7566/jpsj.95.053702

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