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Very large spontaneous electric polarization in BiFeO3 single crystals at room temperature and its evolution under cycling fields

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 نشر من قبل Lo\\\"ic Bervas
 تاريخ النشر 2007
  مجال البحث فيزياء
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Electric polarization loops are measured at room temperature on highly pure BiFeO3 single crystals synthesized by a flux growth method. Because the crystals have a high electrical resistivity, the resulting low leakage currents allow us to measure a large spontaneous polarization reaching 100 microC.cm^{-2}, a value never reported in the bulk. During electric cycling, the slow degradation of the material leads to an evolution of the hysteresis curves eventually preventing full saturation of the crystals.



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