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arXiv · 1203.1200

Dielectric properties of charge ordered LuFe2O4 revisited: The apparent influence of contacts

Daniel Niermann·Florian Waschkowski·Joost de Groot·Manuel Angst·Joachim Hemberger
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Abstract

We show results of broadband dielectric measurements on the charge ordered, proposed to be mul- tiferroic material LuFe2O4. The temperature and frequency dependence of the complex permittivity as investigated for temperatures above and below the charge-oder transition near T_CO ~ 320 K and for frequencies up to 1 GHz can be well described by a standard equivalent-circuit model considering Maxwell-Wagner-type contacts and hopping induced AC-conductivity. No pronounced contribution of intrinsic dipolar polarization could be found and thus the ferroelectric character of the charge order in LuFe2O4 has to be questioned.

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Daniel Niermann, Florian Waschkowski, Joost de Groot, Manuel Angst, Joachim Hemberger. 2012-03-06. Dielectric properties of charge ordered LuFe2O4 revisited: The apparent influence of contacts. https://doi.org/10.1103/physrevlett.109.016405

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