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arXiv · 1208.3326

Site-selective quantum correlations revealed by magnetic anisotropy in the tetramer system SeCuO3

I. Živković·D. M. Djokić·M. Herak·D. Pajić·K. Prša·P. Pattison·D. Dominko·Z. Micković·D. Cinčić·L. Forro·H. Berger·H. M. Ronnow
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Abstract

We present the investigation of a monoclinic compound SeCuO3 using x-ray powder diffraction, magnetization, torque and electron-spin-resonance (ESR). Structurally based analysis suggests that SeCuO3 can be considered as a 3D network of tetramers. The values of intra-tetramer exchange interactions are extracted from the temperature dependence of the susceptibility and amount to ~200 K. The inter-tetramer coupling leads to the development of long-range antiferromagnetic order at TN = 8 K. An unusual temperature dependence of the effective g-tensors is observed, accompanied with a rotation of macroscopic magnetic axes. We explain this unique observation as due to site-selective quantum correlations.

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I. Živković, D. M. Djokić, M. Herak, D. Pajić, K. Prša, P. Pattison, D. Dominko, Z. Micković, D. Cinčić, L. Forro, H. Berger, H. M. Ronnow. 2012-08-16. Site-selective quantum correlations revealed by magnetic anisotropy in the tetramer system SeCuO3. https://doi.org/10.1103/physrevb.86.054405

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