Journal Article

FZJ-2021-05040

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Ordering of Oxygen Vacancies and Related Ferroelectric Properties in HfO 2 − δ

Rushchanskii, K. (Corresponding author)FZJ* ; Blügel, S.FZJ* ; Ležaić, M.FZJ*

2021
APS College Park, Md.

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Please use a persistent id in citations: http://hdl.handle.net/2128/29401  doi:10.1103/PhysRevLett.127.087602

Abstract: Using density functional theory combined with an evolutionary algorithm, we investigate ferroelectricity in substoichiometric HfO2−δ with fixed composition δ=0.25. We find that oxygen vacancies tend to cluster in the form of two-dimensional extended defects, revealing several patterns of local relative arrangements within an energy range of 100 meV per Hf atom. Two lowest-energy patterns result in polar monoclinic structures with different transformation properties. The lowest one elastically transforms to the ferroelectric orthorhombic structure via a shear deformation, overcoming an energy barrier, which is more than twice lower than in the stoichiometric hafnia. The second-lowest structure transforms at smaller volumes to a nonpolar tetragonal one. We discuss the experimentally observed wake-up effect, fatigue, and imprint in HfO2-based ferroelectrics in terms of different local ordering of oxygen-vacancy extended defects, which favor specific crystallographic phases.

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Contributing Institute(s):

1. Quanten-Theorie der Materialien (IAS-1)
2. Quanten-Theorie der Materialien (PGI-1)
3. JARA-FIT (JARA-FIT)
4. JARA - HPC (JARA-HPC)

Research Program(s):

1. 5211 - Topological Matter (POF4-521) (POF4-521)

Appears in the scientific report 2021

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Database coverage:
; ; ; Clarivate Analytics Master Journal List ; Current Contents - Electronics and Telecommunications Collection ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF >= 5 ; JCR ; Nationallizenz ; SCOAP3 sponsored Journal ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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