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Control of ferroelectric phase by chemical pressure in (Gd,Tb)MnO$_{3}$ crystals

K. Noda·S. Nakamura·H. Kuwahara
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Abstract

We have investigated the dielectric properties of Gd$_{1-x}$Tb$_{x}$MnO$_{3}$ crystals in magnetic fields to clarify the crossover between two distinct ferroelectric phases, GdMnO$_{3}$-type (first-order displacive) and TbMnO$_{3}$-type (second-order order-disorder). We have found that the compositional phase boundary between the phases exists around 0.3$<$$x$$<$0.4. For the $x$=0.1 sample exposed to magnetic fields above 3T, we have discovered successive ferroelectric phase transitions that occur at two different temperatures. We have determined the electric and magnetic phase diagram for $x$$=$0, 0.1, and 0.3 in the plane of temperature and field in order to demonstrate the change in the ferroelectric phases.

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K. Noda, S. Nakamura, H. Kuwahara. 2005-04-26. Control of ferroelectric phase by chemical pressure in (Gd,Tb)MnO$_{3}$ crystals. https://doi.org/10.1109/tmag.2005.854835

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