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Pressure-induced insulating state in (La,Sr)CoO$_{3}$

R. Lengsdorf·M. Ait-Tahar·S. S. Saxena·M. Ellerby·D. I. Khomskii·H. Micklitz·T. Lorenz·M. M. Abd-Elmeguid
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Abstract

We have investigated the effect of pressure on the electronic, magnetic, and structural properties on a single crystal of conducting, ferromagnet (T$_{C}$=157K) La$_{0.82}$Sr$_{0.18}$CoO$_{3}$ located near the boundary of the metal-insulator transition. Contrary to the results reported on related systems, we find a transition from the conducting state to an insulating state and a decrease of T$_{C}$ with increasing pressure while the lattice structure remains unchanged. We show that this unusual behavior is driven by a gradual change of the spin state of Co$^{3+}$ ions from magnetic intermediate-spin (t$_{2g}^5$e$_{g}^{1}$; S=1) to a nonmagnetic low-spin (t$_{2g}^6$e$_{g}^{0}$; S=0) state.

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R. Lengsdorf, M. Ait-Tahar, S. S. Saxena, M. Ellerby, D. I. Khomskii, H. Micklitz, T. Lorenz, M. M. Abd-Elmeguid. 2005-04-12. Pressure-induced insulating state in (La,Sr)CoO$_{3}$. https://doi.org/10.1103/physrevb.69.140403

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