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arXiv · 1403.0614

CaBaCo$_4$O$_7$ : A ferrimagnetic pyroelectric

R. D. Johnson·K. Cao·P. G. Radaelli
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Abstract

Magneto-electric coupling in pyroelectric CaBaCo$_4$O$_7$ is investigated using ab-intio calculations and Landau theory. The former shows that exchange-striction is strong enough to produce a giant change in electric polarization upon ferrimagnetic ordering, comparable to the experimentally determined value of ~17 mC/m$^2$ . Furthermore, Landau theory demonstrates that magneto-elastic coupling in CaBaCo$_4$O$_7$ is responsible for the strong magneto-electric coupling appearing close to the magnetic phase transition.

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R. D. Johnson, K. Cao, P. G. Radaelli. 2014-03-03. CaBaCo$_4$O$_7$ : A ferrimagnetic pyroelectric. https://doi.org/10.1103/physrevb.90.045129

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