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arXiv · 1106.0662

Quasi-one-dimensional antiferromagnetism and multiferroicity in CuCrO$_4$

J. M. Law·P. Reuvekamp·R. Glaum·C. Lee·J. Kang·M. -H. Whangbo·R. K. Kremer
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Abstract

The bulk magnetic properties of the new quasi-one-dimensional Heisenberg antiferromagnet, CuCrO$_4$, were characterized by magnetic susceptibility, heat capacity, optical spectroscopy, EPR and dielectric capacitance measurements and density functional evaluations of the intra- and interchain spin exchange interactions. We found type-II multiferroicity below the Néel temperature of 8.2(5) K, arising from competing antiferromagnetic nearest-neighbor ($J_{\rm nn}$) and next-nearest-neighbor ($J_{\rm nnn}$) intra-chain spin exchange interactions. Experimental and theoretical results indicate that the ratio $J_{\rm nn}/J_{\rm nnn}$ is close to 2, putting CuCrO$_4$ in the vicinity of the Majumdar-Ghosh point.

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J. M. Law, P. Reuvekamp, R. Glaum, C. Lee, J. Kang, M. -H. Whangbo, R. K. Kremer. 2011-06-03. Quasi-one-dimensional antiferromagnetism and multiferroicity in CuCrO$_4$. https://doi.org/10.1103/physrevb.84.014426

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