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Oxygen deficiency and valency reconstruction in multiferroic V-doped HfO2

Vincenzo Fiorentini

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Phys. Rev. Materials 10, 104412 – Published 15 October, 2026

DOI: https://doi.org/10.1103/dfcj-rb7w

Abstract

The interplay of oxygen deficiency and vanadium multiple valency in the candidate multiferroic V-doped Pca21 hafnia HfO2 is studied by first-principles calculations. Low-lying V majority gap states accept electrons from oxygen-vacancy donors, reducing their formation energy, and converting nominal V4+ centers into V3+. The resulting local magnetization and screening changes are reflected in the calculated V core-level shifts, which are consistent with the experimentally observed x-ray photoelectron spectroscopy signatures. The calculated V3+/V4+ population ratio determined by oxygen vacancies only matches experiment in reducing conditions, suggesting that additional electron reservoirs may contribute under atomic-layer-deposition growth conditions. A similar scenario also seems to apply to the recently observed multiferroicity in Cr-doped hafnia, where oxygen deficiency is expected from the synthesis route.

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References (19)

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Phys. Rev. Materials 10, 104412– Published 15 October, 2026
  • Received 11 June 2026
  • Accepted 24 September 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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