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arXiv · 2107.08261

Re-entrant phenomenon in diffuse ferroelectric, $BaSn_{0.15}Ti_{0.85}O_{3}$ : Local structural insights and FORC study

Akash Surampalli·Ramon Egli·Deepak Prajapat·Carlo Meneghini·V. Raghavendra Reddy
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Abstract

From the phase diagram as proposed by Lei et.al., [J. App. Phys 101, 084105 (2007)] a $BaSn_{0.15}Ti_{0.85}O_{3}$ is chosen showing a diffuse phase transition between cubic to rhombohedral (C-R) near room temperature. Dielectric analysis confirms a phase transition near room temperature ($T_{C}$ $\approx$ 290 K) and also frequency dispersion in dielectric constant is observed towards low temperature. Polarization and first-order reversal curves (FORC) suggest that the system is in re-entrant phase at low temperatures. Put together, all these electrical characterization results points toward the relaxor behavior in the re-entrant phase. Local probe techniques such as x-ray absorption near edge spectroscopy, Raman and Mossbauer spectroscopy are employed to investigate the local environment changes around this region of low temperature dielectric anomaly. A simple ferroelectric exchange model explaining the low temperature re-entrant behavior is presented from these results.

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Akash Surampalli, Ramon Egli, Deepak Prajapat, Carlo Meneghini, V. Raghavendra Reddy. 2021-07-17. Re-entrant phenomenon in diffuse ferroelectric, $BaSn_{0.15}Ti_{0.85}O_{3}$ : Local structural insights and FORC study. https://doi.org/10.1103/physrevb.104.184114

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