The potential for creating hierarchical domain structures, or mixtures of energetically degenerate phases with distinct patterns that can be modified continually, in ferroelectric thin films offers a pathway to control their mesoscale structure beyond lattice‐mismatch strain with a substrate. Here, it is demonstrated that varying the strontium content provides deterministic strain‐driven control of hierarchical domain structures in Pb1−
The hafnate perovskites PbHfO3(antiferroelectric) and SrHfO3(“potential” ferroelectric) are studied as epitaxial thin films on SrTiO3(001) substrates with the added opportunity of observing a morphotropic phase boundary (MPB) in the Pb1−
- Award ID(s):
- 1708615
- NSF-PAR ID:
- 10361827
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 34
- Issue:
- 1
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract x Srx TiO3 solid‐solution thin films wherein two types,c /a anda 1/a 2, of nanodomains can coexist. Combining phase‐field simulations, epitaxial thin‐film growth, detailed structural, domain, and physical‐property characterization, it is observed that the system undergoes a gradual transformation (with increasing strontium content) from droplet‐likea 1/a 2 domains in ac /a domain matrix, to a connected‐labyrinth geometry ofc /a domains, to a disconnected labyrinth structure of the same, and, finally, to droplet‐likec /a domains in ana 1/a 2 domain matrix. A relationship between the different mixed‐phase modulation patterns and its topological nature is established. Annealing the connected‐labyrinth structure leads to domain coarsening forming distinctive regions of parallelc /a anda 1/a 2 domain stripes, offering additional design flexibility. Finally, it is found that the connected‐labyrinth domain patterns exhibit the highest dielectric permittivity. -
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