• Balke, Nina
• Vasudevan, Rama K.
• Rama Damodaran, Anoop
• Kim, Jieun
• Kalinin, Sergei V.
• Dedon, Liv R.
• Mccarter, Margaret R.
• Jesse, Stephen
• Cao, Ye
• Agar, Josh C.
• Pandya, Shishir
• Li, Qian
• Saremi, Sahar
• Xu, Ruijuan
• Martin, Lane W.
• Angsten, Tom
• Asta, Mark

Abstract

<jats:p>Leveraging competition between energetically degenerate states to achieve large field‐driven responses is a hallmark of functional materials, but routes to such competition are limited. Here, a new route to such effects involving domain‐structure competition is demonstrated, which arises from strain‐induced spontaneous partitioning of PbTiO<jats:sub>3</jats:sub> thin films into nearly energetically degenerate, hierarchical domain architectures of coexisting <jats:italic>c/a</jats:italic> and <jats:italic>a<jats:sub>1</jats:sub></jats:italic>/<jats:italic>a<jats:sub>2</jats:sub></jats:italic> domain structures. Using band‐excitation piezoresponse force microscopy, this study manipulates and acoustically detects a facile interconversion of different ferroelastic variants via a two‐step, three‐state ferroelastic switching process (out‐of‐plane polarized <jats:italic>c</jats:italic><jats:sup>+</jats:sup> → in‐plane polarized <jats:italic>a</jats:italic> → out‐of‐plane polarized <jats:italic>c</jats:italic><jats:sup>−</jats:sup> state), which is concomitant with large nonvolatile electromechanical strains (≈1.25%) and tunability of the local piezoresponse and elastic modulus (&gt;23%). It is further demonstrated that deterministic, nonvolatile writing/erasure of large‐area patterns of this electromechanical response is possible, thus showing a new pathway to improved function and properties.</jats:p>

Topics

• impedance spectroscopy
• thin film
• microscopy