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Charge-stripe order in the electronic ferroelectric LuFe2O4

Y. Zhang·H. X. Yang·C. Ma·H. F. Tian·J. Q. Li *
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Abstract

The structural features of the charge ordering states in LuFe2O4 are characterized by in-situ cooling TEM observations from 300K down to 20K. Two distinctive structural modulations, a major q1= (1/3, 1/3, 2) and a weak q2=q1/10 + (0, 0, 3/2), have been well determined at the temperature of 20K. Systematic analysis demonstrates that the charges at low temperatures are well crystallized in a charge stripe phase, in which the charge density wave behaviors in a non-sinusoidal fashion resulting in elemental electric dipoles for ferroelectricity. It is also noted that the charge ordering and ferroelectric domains often change markedly with lowering temperatures and yields a rich variety of structural phenomena.

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Y. Zhang, H. X. Yang, C. Ma, H. F. Tian, J. Q. Li *. 2007-02-26. Charge-stripe order in the electronic ferroelectric LuFe2O4. https://doi.org/10.1103/physrevlett.98.247602

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