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arXiv · 0902.4808

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

Barnali Ghosh·Dipten Bhattacharya·A. K. Raychaudhuri·S. Arumugam
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Abstract

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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Barnali Ghosh, Dipten Bhattacharya, A. K. Raychaudhuri, S. Arumugam. 2009-02-27. Frequency dependence of dielectric anomaly around Neel temperature in bilayer manganite Pr(Sr0.1Ca0.9)2Mn2O7. https://doi.org/10.1063/1.3153124

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