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arXiv · 1906.06219

FeTi$_2$O$_5$: a spin Jahn-Teller transition enhanced by cation substitution

Franz Lang·Lydia Jowitt·Dharmalingam Prabhakaran·Roger D. Johnson·Stephen J. Blundell
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Abstract

We have used muon-spin rotation, heat capacity and x-ray diffraction measurements in combination with density functional theory and dipole field calculations to investigate the crystal and magnetic structure of FeTi$_2$O$_5$. We observe a long range ordered state below $T_{\rm N}$=41.8(5) K with indications of significant correlations existing above this temperature. We determine candidate muon stopping sites in this compound, and find that our data are consistent with the spin Jahn-Teller driven antiferromagnetic ground state with $\boldsymbol{k}$=(1/2,1/2,0) reported for CoTi$_2$O$_5$ ($T_{\rm N}$=26 K). By comparing our data with calculated dipolar fields we can restrict the possible moment size and directions of the Fe$^{2+}$ ions.

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Franz Lang, Lydia Jowitt, Dharmalingam Prabhakaran, Roger D. Johnson, Stephen J. Blundell. 2019-08-15. FeTi$_2$O$_5$: a spin Jahn-Teller transition enhanced by cation substitution. https://doi.org/10.1103/physrevb.100.094401

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