Defect Chemistry of Hafnia-Based Ferroelectrics under Oxide-Electrode Constraints
Abstract
HfO2 heterostructures with La0.67Sr0.33MnO3 (LSMO) epitaxial electrodes have attracted interest as ferroelectric systems with electrode-dependent defect chemistry. However, the formation and stability of defects under LSMO-constrained chemical conditions remain poorly understood. In this work, we use density functional theory calculations to systematically investigate oxygen vacancies and La-, Sr-, and Mn-related interstitial and substitutional defects in HfO2 under chemical environments constrained by the LSMO electrode. We find that LSMO stability substantially narrows the accessible O chemical potential range relative to bulk HfO2, altering the predicted defect formation energies. While La and Sr substitutional defects are governed primarily by preferred ionic valence states, oxygen vacancies and Mn substitutional defects exhibit charge states sensitive to the local atomic environment. In addition, defect-complex calculations in orthorhombic HfO2 reveal negative binding energies, indicating favorable defect association. The La- and Mn-related defect complexes exhibit thermodynamic competition, with their relative stability depending on the Fermi level and oxygen chemical potential. Lastly, extending the analysis to Hf0.5Zr0.5O2 and ZrO2 reveals common oxygen-vacancy trends, while the stability of LSMO-derived defects depends more strongly on the host material and crystal phase. These results provide a thermodynamic basis for understanding how electrode-constrained chemical environments and host structures influence defect formation, charge compensation, and defect-complex stability in HfO2-based materials.
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BibTeX
@misc{jeon2026defect,
title = {{Defect Chemistry of Hafnia-Based Ferroelectrics under Oxide-Electrode Constraints}},
author = {Sehyeok Jeon and Aloysius Soon and Yongjin Shin},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2611.02317},
eprint = {2611.02317},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2611.02317},
}
RIS
TY - UNPB
TI - Defect Chemistry of Hafnia-Based Ferroelectrics under Oxide-Electrode Constraints
AU - Sehyeok Jeon
AU - Aloysius Soon
AU - Yongjin Shin
PY - 2026
DA - 2026/11/02
PB - arXiv
DO - 10.48550/arxiv.2611.02317
UR - https://arxiv.org/abs/2611.02317
AB - HfO_2 heterostructures with La_0.67Sr_0.33MnO_3 (LSMO) epitaxial electrodes have attracted interest as ferroelectric systems with electrode-dependent defect chemistry. However, the formation and stability of defects under LSMO-constrained chemical conditions remain poorly understood. In this work, we use density functional theory calculations to systematically investigate oxygen vacancies and La-, Sr-, and Mn-related interstitial and substitutional defects in HfO_2 under chemical environments constrained by the LSMO electrode. We find that LSMO stability substantially narrows the accessible O chemical potential range relative to bulk HfO_2, altering the predicted defect formation energies. While La and Sr substitutional defects are governed primarily by preferred ionic valence states, oxygen vacancies and Mn substitutional defects exhibit charge states sensitive to the local atomic environment. In addition, defect-complex calculations in orthorhombic HfO_2 reveal negative binding energies, indicating favorable defect association. The La- and Mn-related defect complexes exhibit thermodynamic competition, with their relative stability depending on the Fermi level and oxygen chemical potential. Lastly, extending the analysis to Hf_0.5Zr_0.5O_2 and ZrO_2 reveals common oxygen-vacancy trends, while the stability of LSMO-derived defects depends more strongly on the host material and crystal phase. These results provide a thermodynamic basis for understanding how electrode-constrained chemical environments and host structures influence defect formation, charge compensation, and defect-complex stability in HfO_2-based materials.
ER -