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Observation of the antiferroquadrupolar order in DyB2C2 by resonant x-ray scattering

T. Matsumura·N. Oumi·K. Hirota·H. Nakao·Y. Murakami·Y. Wakabayashi·T. Arima·S. Ishihara·Y. Endoh
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Abstract

We have investigated the antiferroquadrupolar(AFQ) order in DyB$_2$C$_2$ by resonant x-ray scattering. X-rays with energies near the $L_3$ absorption edge of Dy were employed. Superlattice peaks that correspond to three kinds of propagation vectors of (1 0 0), (1 0 1/2) and (0 0 1/2) were investigated in detail with polarization analyses. The experimental results are analyzed using a formalism on resonant x-ray scattering and a model of the AFQ order. The magnetic and quadrupolar scatterings are explained by the model satisfactorily. A detailed investigation on the critical behavior of the AFQ ordering is also reported. The critical exponent $β$ is deduced to be 0.35, not far from the three-dimensional Heisenberg system. We have also succeeded in detecting the diffuse scattering above $T_{Q}$.

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T. Matsumura, N. Oumi, K. Hirota, H. Nakao, Y. Murakami, Y. Wakabayashi, T. Arima, S. Ishihara, Y. Endoh. 2001-10-08. Observation of the antiferroquadrupolar order in DyB2C2 by resonant x-ray scattering. https://doi.org/10.1103/physrevb.65.094420

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