Nanoscale Origins of Ferroelastic Domain Wall Mobility in Ferroelectric Multilayers

Journal Article · Mon Oct 31 00:00:00 EDT 2016 · ACS Nano

DOI:https://doi.org/10.1021/acsnano.6b05180· OSTI ID:1336210

Huang, Hsin-Hui ^[1]; Hong, Zijian ^[2]; Xin, Huolin L. ^[3]; Su, Dong ^[3]; Chen, Long-Qing ^[2]; Huang, Guanzhong ^[4]; Munroe, Paul R. ^[1]; Valanoor, Nagarajan ^[1]

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1. Univ. of New South Wales, Sydney, NSW (Australia). School of Materials Science and Engineering
2. Pennsylvania State Univ., University Park, PA (United States). Dept of Materials Science and Engineering
3. Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)
4. Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN); Stony Brook Univ., NY (United States). Dept. of Materials Science and Engineering

Here we investigate the nanoscale origins of ferroelastic domain wall motion in ferroelectric multilayer thin films that lead to giant electromechanical responses. We present direct evidence for complex underpinning factors that result in ferroelastic domain wall mobility using a combination of atomic-level aberration corrected scanning transmission electron microscopy and phase-field simulations in model epitaxial (001) tetragonal (T) PbZr_xTi_1-xO₃ (PZT)/rhombohedral (R) PbZr_xTi_1-xO₃ (PZT) bilayer heterostructures. The local electric dipole distribution is imaged on an atomic scale for a ferroelastic domain wall that nucleates in the R-layer and cuts through the composition breaking the T/R interface. Our studies reveal a highly complex polarization rotation domain structure that is nearly on the knife-edge at the vicinity of this wall. Induced phases, namely tetragonal-like and rhombohedral-like monoclinic were observed close to the interface, and exotic domain arrangements, such as a half-four-fold closure structure, are observed. Phase field simulations show this is due to the minimization of the excessive elastic and electrostatic energies driven by the enormous strain gradient present at the location of the ferroelastic domain walls. Thus, in response to an applied stimulus, such as an electric field, any polarization reorientation must minimize the elastic and electrostatic discontinuities due to this strain gradient, which would induce a dramatic rearrangement of the domain structure. This insight into the origins of ferroelastic domain wall motion will allow researchers to better “craft” such multilayered ferroelectric systems with precisely tailored domain wall functionality and enhanced sensitivity, which can be exploited for the next generation of integrated piezoelectric technologies.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0012704; FG02-07ER46417; DMR-1420620; DMR-1210588
• OSTI ID: 1336210
• Report Number(s): BNL-113228-2016-JA; R&D Project: 16060; 16060; KC0403020
• Journal Information: ACS Nano, Vol. 10, Issue 11; ISSN 1936-0851
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
aberration-corrected scanning transmission electron microscopy
epitaxial thin films
ferroelastic domains
nanoscale electromechanics
nanoscale ferroelectrics