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arXiv · 1310.7804

Spin correlations and Dzyaloshinskii-Moriya interaction in Cs$_2$CuCl$_4$

M. A. Fayzullin·R. M. Eremina·M. V. Eremin·A. Dittl·N. van Well·F. Ritter·W. Assmus·J. Deisenhofer·H. -A. Krug von Nidda·A. Loidl
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Abstract

We report on electron spin resonance (ESR) studies of the spin relaxation in Cs$_2$CuCl$_4$. The main source of the ESR linewidth at temperatures $T \leq 150$ K is attributed to the uniform Dzyaloshinskii-Moriya interaction. The vector components of the Dzyaloshinskii-Moriya interaction are determined from the angular dependence of the ESR spectra using a high-temperature approximation. Both the angular and temperature dependence of the ESR linewidth have been analyzed using a self-consistent quantum-mechanical approach. In addition analytical expressions based on a quasi-classical picture for spin fluctuations are derived, which show good agreement with the quantum-approach for temperatures $T \geq 2J/k_{\rm B} \approx 15$ K. A small modulation of the ESR linewidth observed in the $ac$-plane is attributed to the anisotropic Zeeman interaction, which reflects the two magnetically nonequivalent Cu positions.

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M. A. Fayzullin, R. M. Eremina, M. V. Eremin, A. Dittl, N. van Well, F. Ritter, W. Assmus, J. Deisenhofer, H. -A. Krug von Nidda, A. Loidl. 2013-10-29. Spin correlations and Dzyaloshinskii-Moriya interaction in Cs$_2$CuCl$_4$. https://doi.org/10.1103/physrevb.88.174421

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