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Abstract Vertically aligned nanocomposite (VAN) thin films offer exceptional physical properties through diverse material combinations, providing a robust platform for designing complex nanocomposites with tailored performance. Considering materials compatibility issues, most of oxide‐metal VANs have focused on noble metals as the secondary phase in the oxide matrix. Here, an oxide‐metal hybrid metamaterials in the VAN form has been designed which combines ferroelectric BaTiO3(BTO) with two immiscible non‐noble metal elements of Co and Cu, resulting in a three‐phase BTO‐Co‐Cu (BTO‐CC) VAN film. This film exhibits a characteristic nanopillar‐in‐matrix nanostructure with three distinct types of nanopillar morphologies, i.e., Co‐rich cylindrical nanopillars, Cu‐Co‐nanolaminated Co rectangular nanopillars and Co‐Cu‐core–shell cylindrical nanopillars. Phase field modeling indicates the constructed structure is resulted from the interplay between thermochemical, chemomechanical, and interfacial energy driving forces. The strong structural anisotropy leads to anisotropic optical and magnetic properties, presenting potential as hyperbolic metamaterial (HMM) with transverse‐positive dispersion in the near‐infrared region. The inclusion of non‐noble Cu nanostructure induces surface plasmon resonance (SPR) in the visible region. Additionally, ferroelectric properties have been demonstrated in a BTO/BTO‐CC bilayer, confirming room‐temperature multiferroicity in the film. The complex three‐phase VANs offer a novel platform for exploring electro‐magneto‐optical coupling along vertical interfaces toward future integrated devices.
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Ferroelectric/multiferroic self-assembled vertically aligned nanocomposites: Current and future status
Even a century after the discovery of ferroelectricity, the quest for the novel multifunctionalities in ferroelectric and multiferroics continues unbounded. Vertically aligned nanocomposites (VANs) offer a new avenue toward improved (multi)functionality, both for fundamental understanding and for real-world applications. In these systems, vertical strain effects, interfaces, and defects serve as key driving forces to tune properties in very positive ways. In this Perspective, the twists and turns in the development of ferroelectric/multiferroics oxide–oxide and unconventional metal–oxide VANs are highlighted. In addition, the future trends and challenges to improve classic ferroelectric/multiferroic VANs are presented, with emphasis on the enhanced functionalities offered by existing VANs, as well as those in emerging systems.
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- PAR ID:
- 10594669
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- APL Materials
- Volume:
- 9
- Issue:
- 3
- ISSN:
- 2166-532X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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