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Spin singlet small bipolarons in Nb-doped BaTiO3

T. Kolodiazhnyi·S. C. Wimbush
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Abstract

The magnetic susceptibility and electrical resistivity of n-type BaTi{1-x}Nb{x}O3 have been measured over a wide temperature range. It is found that, for 0 < x < 0.2, dopant electrons form immobile spin singlet small bipolarons with binding energy around 110 meV. For x = 0.2, a maximum in the electrical resistivity around 15 K indicates a crossover from band to hopping transport of the charge carriers, a phenomenon expected but rarely observed in real polaronic systems.

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T. Kolodiazhnyi, S. C. Wimbush. 2006-05-18. Spin singlet small bipolarons in Nb-doped BaTiO3. https://doi.org/10.1103/physrevlett.96.246404

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