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arXiv · 1705.01324

Anisotropic Exchange in ${\bf LiCu_2O_2}$

Zakir Seidov·Tatiana P. Gavrilova·Rushana M. Eremina·Leonid E. Svistov·Alexander A. Bush·Alois Loidl·Hans-Albrecht Krug von Nidda
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Abstract

We investigate the magnetic properties of the multiferroic quantum-spin system LiCu$_2$O$_2$ by electron spin resonance (ESR) measurements at $X$- and $Q$-band frequencies in a wide temperature range $(T_{\rm N1} \leq T \leq 300$\,K). The observed anisotropies of the $g$ tensor and the ESR linewidth in untwinned single crystals result from the crystal-electric field and from local exchange geometries acting on the magnetic Cu$^{2+}$ ions in the zigzag-ladder like structure of LiCu$_2$O$_2$. Supported by a microscopic analysis of the exchange paths involved, we show that both the symmetric anisotropic exchange interaction and the antisymmetric Dzyaloshinskii-Moriya interaction provide the dominant spin-spin relaxation channels in this material.

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Zakir Seidov, Tatiana P. Gavrilova, Rushana M. Eremina, Leonid E. Svistov, Alexander A. Bush, Alois Loidl, Hans-Albrecht Krug von Nidda. 2017-05-03. Anisotropic Exchange in ${\bf LiCu_2O_2}$. https://doi.org/10.1103/physrevb.95.224411

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