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Superparaelectric phase in the ensemble of non-interacting ferroelectric nanoparticles

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 نشر من قبل Anna Morozovska Nickolaevna
 تاريخ النشر 2008
  مجال البحث فيزياء
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For the first time we predict the conditions of superparaelectric phase appearance in the ensemble of non-interacting spherical ferroelectric nanoparticles. The superparaelectricity in nanoparticle was defined by analogy with superparamagnetism, obtained earlier in small nanoparticles made of paramagnetic material. Calculations of correlation radius, energetic barriers of polarization reorientation and polarization response to external electric field, were performed within Landau-Ginzburg phenomenological approach for perovskites Pb(Zr,Ti)O3, BiFeO3 and uniaxial ferroelectrics rochelle salt and triglycine sulfate.

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