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Frequency dependence of dielectric anomaly around Neel temperature in bilayer manganite Pr(Sr0.1Ca0.9)2Mn2O7

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 نشر من قبل Dipten Bhattacharya
 تاريخ النشر 2009
  مجال البحث فيزياء
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A novel frequency dependence of anomaly in dielectric constant versus temperature plot, around the Neel temperature T_N (~150 K), has been observed in a single crystal of bilayer manganite Pr(Sr0.1Ca0.9)2Mn2O7. The anomaly in the permittivity (epsilon||c) occurs at a temperature T_f which moves within a temperature window (delT_f) of ~40 K around T_N for a frequency range 50 kHz-5 MHz. The capacitive component Cp of the dielectric response exhibits a clear yet broad feature around T_N which establishes the intrinsic capacitive nature of the anomaly.

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