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Ground state order and spin-lattice coupling in tetrahedral spin systems Cu2Te2O5X2

M. Prester·A. Smontara·I. Zivkovic·A. Bilusic·D. Drobac·H. Berger·F. Bussy
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Abstract

High-resolution ac susceptibility and thermal conductivity measurement on Cu2Te2O5X2(X=Br,Cl) single crystals are reported. For Br-sample, sample dependence prevents to distinguish between possibilities of magnetically ordered and spin-singlet ground states. In Cl-sample a three-dimensional transition at 18.5 K is accompanied by almost isotropic behavior of susceptibility and almost switching behavior of thermal conductivity. Thermal conductivity studies suggest the presence of a tremendous spin-lattice coupling characterizing Cl- but not Br-sample. Below the transition Cl-sample is in a complex magnetic state involving AF order but also the elements consistent with the presence of a gap in the excitation spectrum.

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M. Prester, A. Smontara, I. Zivkovic, A. Bilusic, D. Drobac, H. Berger, F. Bussy. 2004-04-06. Ground state order and spin-lattice coupling in tetrahedral spin systems Cu2Te2O5X2. https://doi.org/10.1103/physrevb.69.180401

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