Temperature dependence of ferroelectric properties and the activation energy of polarization reversal in (Pr,Mn)‐codoped BiFeO₃ thin films

Abstract

We applied Vopsaroiu's model to (Bi,Pr)(Fe,Mn)O3 (BPFM) and Pb(Zr,Ti)O3 (PZT) ferroelectric thin films fabricated by chemical solution deposition. Temperature dependences of the saturation polarization and the coercive filed were measured in low temperature region from 100 to 200 K. The saturation polarizations of BPFM thin films were decreased with decreasing the measurement temperature due to polarization pinning effect while that of PZT thin film was almost unchanged over the temperature region. The coercive fields of all the thin films were increased linearly with decreasing the measurement temperature. The activation energies for polarization reversal in as-grown BPFM, post-annealed BPFM and PZT thin films were 1.18, 1.25, 0.95 eV, respectively. These results indicate that BPFM thin films have large activation energies for polarization reversal compared with PZT thin film. In addition, the post-annealed BPFM thin film has a larger activation energy than the as-grown BPFM thin film.

Giant Enhancement of Polarization and Strong Improvement of Retention in Epitaxial Ba0.6Sr0.4TiO3‐Based Nanocomposites

“…At 125 °C, R ( T ) values as high as 89% and 93% were obtained for the x = 0.50 and x = 0.75 films. These values are comparable to 89% measured in epitaxial Pb(Zr 0.52 Ti 0.48 )O 3 films at the same temperature . Both the x = 0.50 and x = 0.75 films maintain their retentions with 74% and 58% values measured at 375 °C.…”

“…The x = 0.75 sample demonstrates a very low temperature coefficient of polarization retention of 0.07% °C −1 (up to 375 °C) which compares to 0.24% °C −1 for the x = 0 (plain BSTO) film. This temperature coefficient of polarization retention for the x = 0.75 sample is similar to the 0.09% °C −1 value for Pb(Zr,Ti)O 3 films . Normally, as the structural dimensions of ferroelectrics are scaled down, polarization (depolarization), dielectric permittivity, and Curie temperature are all reduced compared to bulk .…”

Physical reality of the Preisach model for organic ferroelectrics

“…This TA-NLS theory has been successfully applied to analyze the switching processes in inorganic as well as organic ferroelectrics 29 , 30 , 42 , 43 . Importantly, it is compatible with the idea of energetic disorder and can be modified by introducing a distribution in energies and random local fields.…”

Polarization loss in the organic ferroelectric trialkylbenzene-1,3,5-tricarboxamide (BTA)

“…E c E 50 V mm À1 and P r E 85 mC m À2 found for P(VDF:TrFE) at room temperature, 29 for which thin film polarization retention times in the order of several hours have been reported, [30][31][32] and compared to inorganics like BFO and PZT where E c E 50 V mm À1 , P r E 1000 mC m À2 and retention times in thin film can be over 10 4 s with an energy barrier W b = 1.25 eV. 33,34 To further interpret the data in Fig. 3, we use the model by Vopsaroiu et al for the depolarization switching time t sw .…”