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Ferroelectricity and Self-Polarization in Ultrathin Relaxor Ferroelectric Films.

ABSTRACT: We report ferroelectricity and self-polarization in the (001) oriented ultrathin relaxor ferroelectric PMN-PT films grown on Nb-SrTiO3, SrRuO3 and La0.7Sr0.3MnO3, respectively. Resistance-voltage measurements and AC impedance analysis suggest that at high temperatures Schottky depletion width in a 4 nm thick PMN-PT film deposited on Nb-SrTiO3 is smaller than the film thickness. We propose that Schottky interfacial dipoles make the dipoles of the nanometer-sized polar nanoregions (PNRs) in PMN-PT films grown on Nb-SrTiO3 point downward at high temperatures and lead to the self-polarization at room temperature with the assistance of in-plane compressive strain. This work sheds light on the understanding of epitaxial strain effects on relaxor ferroelectric films and self-polarization mechanism.

SUBMITTER: Miao P

PROVIDER: S-EPMC4730210 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Ferroelectricity and Self-Polarization in Ultrathin Relaxor Ferroelectric Films.

Miao Peixian P Zhao Yonggang Y Luo Nengneng N Zhao Diyang D Chen Aitian A Sun Zhong Z Guo Meiqi M Zhu Meihong M Zhang Huiyun H Li Qiang Q

Scientific reports 20160128

We report ferroelectricity and self-polarization in the (001) oriented ultrathin relaxor ferroelectric PMN-PT films grown on Nb-SrTiO3, SrRuO3 and La0.7Sr0.3MnO3, respectively. Resistance-voltage measurements and AC impedance analysis suggest that at high temperatures Schottky depletion width in a 4 nm thick PMN-PT film deposited on Nb-SrTiO3 is smaller than the film thickness. We propose that Schottky interfacial dipoles make the dipoles of the nanometer-sized polar nanoregions (PNRs) in PMN-PT ...[more]

PMID: 26817516

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