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arXiv · 1507.01880

Quantum Critical Point study in Multiferroic Hexaferrites: BaFe12O19, SrFe12O19, and PbFe3Ga9O19 -- Verification of the Khmelnitskii Theory

S. E. Rowley·Yi-sheng Chai·Shi-peng Shen·Young Sun·A. T. Jones·B. E. Watts·J. F. Scott
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Abstract

BaFe12O19 is a popular M-type hexaferrite with T(Neel) = 720 K of enormous commercial value (3 billion dollars/year). It exhibits an incipient ferroelectric phase transition (in violation of the Spaldin-Hill rule) extrapolated to lie at 6.0 K Kelvin but suppressed due to quantum fluctuations (as in SrTiO3). The QCP theory of Khmelnitskii for such uniaxial ferroelectrics predicts that the inverse isothermal electric susceptibility varies as T cubed, in contrast to that for pseudo-cubic materials such as SrTiO3 or KTaO3, a hypothesis we verify.

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S. E. Rowley, Yi-sheng Chai, Shi-peng Shen, Young Sun, A. T. Jones, B. E. Watts, J. F. Scott. 2015-07-07. Quantum Critical Point study in Multiferroic Hexaferrites: BaFe12O19, SrFe12O19, and PbFe3Ga9O19 -- Verification of the Khmelnitskii Theory. https://arxiv.org/abs/1507.01880

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