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arXiv · 1607.02239

Magnetic structure of divalent europium compound EuGa$_4$ studied by single crystal time-of-flight neutron diffraction

Takuro Kawasaki·Koji Kaneko·Ai Nakamura·Naofumi Aso·Masato Hedo·Takao Nakama·Takashi Ohhara·Ryoji Kiyanagi·Kenichi Oikawa·Itaru Tamura·Akiko Nakao·Koji Munakata·Takayasu Hanashima·Yoshichika Ōnuki
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Abstract

The magnetic structure of the intermetallic compound EuGa$_4$ was investigated using single-crystal neutron diffraction with the time-of-flight (TOF) Laue technique on the new diffractometer SENJU at MLF of J-PARC. In spite of high neutron absorption of Eu, a vast number of diffraction spots were observed without isotope enrichment. The magnetic reflections were appeared at the positions with the diffraction indices of $h+k+l{\neq}2n$ below 16 K, indicating that the ordering vector is ${\bf q}=(0~0~0)$. Continuous evolution of magnetic reflection intensity below $T_{\rm N}$ follows a squared Brillouin function for $S$=7/2. By adopting a wavelength-dependent absorption collection, the magnetic structure of EuGa$_4$ was revealed that a nearly full magnetic moment of 6.4$~{\mu}_{\rm B}$ of Eu lies within the basal plane of the lattice. The present study reveals a well-localized divalent Eu magnetism in EuGa$_4$ and demonstrates a high ability of SENJU to investigate materials with high neutron absorption.

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Takuro Kawasaki, Koji Kaneko, Ai Nakamura, Naofumi Aso, Masato Hedo, Takao Nakama, Takashi Ohhara, Ryoji Kiyanagi, Kenichi Oikawa, Itaru Tamura, Akiko Nakao, Koji Munakata, Takayasu Hanashima, Yoshichika Ōnuki. 2016-07-08. Magnetic structure of divalent europium compound EuGa$_4$ studied by single crystal time-of-flight neutron diffraction. https://doi.org/10.7566/jpsj.85.114711

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