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arXiv · 1309.4214

Lattice and polarizability mediated spin activity in EuTiO_3

K. Caslin·R. K. Kremer·Z. Guguchia·H. Keller·J. Köhler·A. Bussmann-Holder
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Abstract

EuTiO_3 is shown to exhibit novel strong spin-charge-lattice coupling deep in the paramagnetic phase. Its existence is evidenced by an, until now, unknown response of the paramagnetic susceptibility at temperatures exceeding the structural phase transition temperature T_S = 282K. The "extra" features in the susceptibility follow the rotational soft zone boundary mode temperature dependence above and below T_S. The theoretical modeling consistently reproduces this behavior and provides reasoning for the stabilization of the soft optic mode other than quantum fluctuations.

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K. Caslin, R. K. Kremer, Z. Guguchia, H. Keller, J. Köhler, A. Bussmann-Holder. 2013-09-17. Lattice and polarizability mediated spin activity in EuTiO_3. https://arxiv.org/abs/1309.4214

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