Electrostriction-driven phase instability enables giant pseudo-piezoelectricity in Hf <sub>0.5</sub> Zr <sub>0.5</sub> O <sub>2X</sub>
The electromechanical properties of hafnium zirconium oxide fluorite (Hf 0.5 Zr 0.5 O 2 , HZO) remain largely unexplored despite its widespread use as a ferroelectric in CMOS-compatible devices. Here, we demonstrate that electrostriction-driven phase instability enables a giant pseudo-piezoelectric response in epitaxial HZO thin films. Above a critical field of 24 kilovolts per centimeter, field-induced transitions between nonpolar and polar phases activate an extrinsic piezoelectric response of ~1000 picometers per volt and bias-stabilized pseudo-piezoelectric strains exceeding 10,000 picometers per volt. This behavior arises from a combination of large electrostriction ( M = 1 × 10 −14 square meters per square volt), ferroelastic softness, and structural reconfiguration, rather than intrinsic polarization switching. Multimodal characterization combining interferometry, diffraction methods, scanning probe microscopy, and first-principles modeling confirms the coupling between strain and metastable phase dynamics. These findings reveal a previously unrecognized mechanism for functional strain generation in fluorite oxides, positioning HZO as a versatile platform for strain-engineered actuators, adaptive metasurfaces, and reconfigurable nanoelectromechanical systems.
Authors
- Achilles Bergne (ORCID: https://orcid.org/0000-0003-4666-8965)
- Vincenzo Esposito (ORCID: https://orcid.org/0000-0002-9817-7810)
- Dennis Valbjørn Christensen (ORCID: https://orcid.org/0000-0003-0048-7595)
- Javier Zamudio‐García (ORCID: https://orcid.org/0000-0001-6717-6762)
- Nini Pryds (ORCID: https://orcid.org/0000-0002-5718-7924)
- Reinis Ignatāns (ORCID: https://orcid.org/0000-0002-0871-4994)
- Henrik Bruus (ORCID: https://orcid.org/0000-0001-5827-2939)
- Megan O. Hill (ORCID: https://orcid.org/0000-0002-7663-7986)
- Ivano E. Castelli (ORCID: https://orcid.org/0000-0001-5880-5045)
- Andréi L. Kholkin (ORCID: https://orcid.org/0000-0003-3432-7610)
- Leonardo Soares de Oliveira (ORCID: https://orcid.org/0000-0001-9999-206X)
- Jesper Wallentin (ORCID: https://orcid.org/0000-0001-5909-0483)
- Dylan Jennings (ORCID: https://orcid.org/0000-0002-5492-8571)
- Milica Vasiljevic (ORCID: https://orcid.org/0000-0003-0629-8760)
- Victor Buratto Tinti (ORCID: https://orcid.org/0000-0001-5759-0214)
- Wolfgang Rheinheimer (ORCID: https://orcid.org/0000-0002-2906-4265)
- Armando Antonio Morin-Martinez (ORCID: https://orcid.org/0000-0002-3391-9967)
- Huaiyu Chen (ORCID: https://orcid.org/0000-0002-5122-486X)
- Mathias Grønborg
- Dimitrios Koukoulis
- Denis Alikin (ORCID: https://orcid.org/0000-0001-9330-7463)
Institutions
- University of Stuttgart (DE)
- Forschungszentrum Jülich (DE)
- Lund University (SE)
- Ernst Ruska Centre (DE)
- Stuttgart Technical University of Applied Sciences (DE)
- MAX IV Laboratory (SE)
- Institute for Advanced Study (DE)
- University of Aveiro (PT)
- Technical University of Munich (DE)
- Ruhr University Bochum (DE)
- University of Latvia (LV)
- Technical University of Denmark (DK)
Publication Details
- Journal
- Science Advances
- Published
- 2026-06-26
- DOI
- https://doi.org/10.1126/sciadv.aea0750
- Primary Topic
- Ferroelectric and Negative Capacitance Devices
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Villum Fonden
- Deutsche Forschungsgemeinschaft
- VINNOVA
- Vetenskapsrådet
- Danmarks Frie Forskningsfond
- Latvijas Zinātnes Padome
- Ministério da Ciência, Tecnologia e Ensino Superior
- Fundació Catalana de Trasplantament
- Novo Nordisk Fonden
- Horizon 2020 Framework Programme
- HORIZON EUROPE Framework Programme
- European Research Council