abstract
In this work, the ferroelectric characteristics of 0.5Ba(Zr0.2Ti0.8)O-3-0.5(Ba0.7Ca0.3)TiO3 (BCZT) thin films grown on 0.7 wt. % Nb-doped (001)-SrTiO3 (Nb:STO) single-crystal have been investigated. High-resolution transmission electron microscopy and electron energy loss spectroscopy revealed a very sharp Nb:STO/BCZT interface, while selected area electron diffraction revealed the epitaxial growth of the BCZT layer on the Nb:STO substrate. The ferroelectric nature of the BCZT films have been investigated by piezoresponse force microscopy and hysteresis loops. The effect of electric field on polarization switching kinetics has been investigated and has been analyzed by the nucleation limited switching model with a Lorentzian distribution function. The local field variation was found to decrease with the increase in the electric field, and thus, the switching process becomes faster. The peak value of the polarization current and the logarithmic characteristic switching time exhibited an exponential dependence on the inverse of electric field. This model gave an excellent agreement with the experimental polarization reversal transients throughout the whole time range. Published by AIP Publishing.
keywords
MECHANISM
subject category
Physics
authors
Silva, JPB; Kamakshi, K; Negrea, RF; Ghica, C; Wang, J; Koster, G; Rijnders, G; Figueiras, F; Pereira, M; Gomes, MJM
our authors
Groups
acknowledgements
This work was supported by (i) Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding No. UID/FIS/04650/2013 and (ii) Project Norte-070124-FEDER-000070 Nanomateriais Multifuncionais. Part of this work was supported by the COST Action MP1308 "Towards Oxide-Based Electronics (TO-BE)." The authors acknowledge the CERIC-ERIC Consortium for access to experimental facilities and financial support under Proposal No. 20157018. The authors J.P.B.S. and F.F. are grateful for financial support through the FCT Grant Nos. SFRH/BPD/92896/2013 and SFRH/BPD/80663/2011, respectively. R.F.N. and C.G. acknowledge the financial support from the Romanian Ministry of Research and Innovation in the frame of the Core Program No. PN18-110101. The authors would also like to acknowledge P. B. Tavares, Centro de Quimica da Universidade de Tras-os-Montes e Alto Douro, for the supply of the 0.5BZT-0.5BCT PLD target.