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arXiv · 0804.3059

Spin-state polaron in lightly hole-doped LaCoO_3

A. Podlesnyak·M. Russina·A. Furrer·A. Alfonsov·E. Vavilova·V. Kataev·B. Büchner·Th. Strässle·E. Pomjakushina·K. Conder·D. I. Khomskii
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Abstract

Inelastic neutron scattering (INS), electron spin (ESR) and nuclear magnetic resonance (NMR) measurements were employed to establish the origin of the strong magnetic signal in lightly hole-doped La_{1-x}Sr_xCoO_3, x=0.002. Both, INS and ESR low temperature spectra show intense excitations with large effective g-factors ~10-18. NMR data indicate the creation of extended magnetic clusters. From the Q-dependence of the INS magnetic intensity we conclude that the observed anomalies are caused by the formation of octahedrally shaped spin-state polarons comprising seven Co ions.

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A. Podlesnyak, M. Russina, A. Furrer, A. Alfonsov, E. Vavilova, V. Kataev, B. Büchner, Th. Strässle, E. Pomjakushina, K. Conder, D. I. Khomskii. 2008-04-18. Spin-state polaron in lightly hole-doped LaCoO_3. https://doi.org/10.1103/physrevlett.101.247603

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