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arXiv · 0811.0744

Giant electro-thermal conductivity and spin-phonon coupling in an antiferromagnetic oxide

C. Chiorescu·J. J. Neumeier·J. L. Cohn
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Abstract

The application of weak electric fields (<~ 100 V/cm) is found to dramatically enhance the lattice thermal conductivity of the antiferromagnetic (AF) insulator CaMnO(3) over a broad range of temperature about the Neel ordering point (125 K). The effect is coincident with field-induced de-trapping of bound electrons, suggesting that phonon scattering associated with short- and long-ranged AF order is suppressed in the presence of the mobilized charge. This interplay between bound charge and spin-phonon coupling might allow for the reversible control of spin fluctuations using weak external fields.

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C. Chiorescu, J. J. Neumeier, J. L. Cohn. 2008-11-05. Giant electro-thermal conductivity and spin-phonon coupling in an antiferromagnetic oxide. https://doi.org/10.1103/physrevlett.101.257202

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