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arXiv · 0811.1391

Anisotropic magnetic diffuse scattering in an easy-plane type antiferromagnet ErNi$_{2}$Ge$_{2}$

Y Tabata·T Yamazaki·M Okue·H Nakamura·M Matsuura
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Abstract

We report on neutron scattering studies of a rare earth intermetallic compound ErNi$_{2}$Ge$_{2}$. Polarized neutron scattering experiments revealed that the magnetic ordered moment ${\bm m}$ lies in ab-plane. Taking account of a lack of the third higher harmonic reflection, ErNi$_{2}$Ge$_{2}$ is considered to have a helical magnetic structure. The magnetic scattering profiles along the $[100]^{\ast}$- and the $[110]^{\ast}$-directions are well described by the sum of Gaussian and modified-Lorentzian terms, even far below $T_{\scriptsize N}$, indicating that short-range orders coexist with a long-range order. Interestingly, the modified-Lorentzian-type diffuse scattering is not present in the profiles along the $[001]^{\ast}$-direction. The anisotropy of the diffuse scattering suggests that the short-range-order consists of one dimensional long-range helices along the c-axis.

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Y Tabata, T Yamazaki, M Okue, H Nakamura, M Matsuura. 2008-11-10. Anisotropic magnetic diffuse scattering in an easy-plane type antiferromagnet ErNi$_{2}$Ge$_{2}$. https://doi.org/10.1088/1742-6596/145/1/012078

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