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arXiv · 0908.2405

Short-range magnetic correlations in Tb5Ge4

W. Tian·A. Kreyssig·J. L. Zarestky·L. Tan·S. Nandi·A. I. Goldman·T. A. Lograsso·D. L. Schlagel·K. A. Gschneidner·V. K. Pecharsky·R. J. McQueeney
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Abstract

We present a single crystal neutron diffraction study of the magnetic short-range correlations in Tb$_5$Ge$_4$ which orders antiferromagnetically below the Neel temperature $T_N$ $\approx$ 92 K. Strong diffuse scattering arising from magnetic short-range correlations was observed in wide temperature ranges both below and above $T_N$. The antiferromagnetic ordering in Tb$_5$Ge$_4$ can be described as strongly coupled ferromagnetic block layers in the $ac$-plane that stack along the b-axis with weak antiferromagnetic inter-layer coupling. Diffuse scattering was observed along both $a^*$ and $b^*$ directions indicating three-dimensional short-range correlations. Moreover, the $q$-dependence of the diffuse scattering is Squared-Lorentzian in form suggesting a strongly clustered magnetic state that may be related to the proposed Griffiths-like phase in Gd$_5$Ge$_4$.

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W. Tian, A. Kreyssig, J. L. Zarestky, L. Tan, S. Nandi, A. I. Goldman, T. A. Lograsso, D. L. Schlagel, K. A. Gschneidner, V. K. Pecharsky, R. J. McQueeney. 2009-08-17. Short-range magnetic correlations in Tb5Ge4. https://doi.org/10.1103/physrevb.80.134422

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