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Influence of tensile-strain-induced oxygen deficiency on metal-insulator transitions in NdNiO_3-? epitaxial thin films.

ABSTRACT: We report direct evidence that oxygen vacancies affect the structural and electrical parameters in tensile-strained NdNiO_3-? epitaxial thin films by elaborately adjusting the amount of oxygen deficiency (?) with changing growth temperature T _D. The modulation in tensile strain and T _D tended to increase oxygen deficiency (?) in NdNiO_3-? thin films; this process relieves tensile strain of the thin film by oxygen vacancy incorporation. The oxygen deficiency is directly correlated with unit-cell volume and the metal-insulator transition temperature (T _MI), i.e., resulting in the increase of both unit-cell volume and metal-insulator transition temperature as oxygen vacancies are incorporated. Our study suggests that the intrinsic defect sensitively influences both structural and electronic properties, and provides useful knobs for tailoring correlation-induced properties in complex oxides.

SUBMITTER: Heo S

PROVIDER: S-EPMC5498495 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Influence of tensile-strain-induced oxygen deficiency on metal-insulator transitions in NdNiO3-δ epitaxial thin films.

Heo Seungyang S Oh Chadol C Son Junwoo J Jang Hyun Myung HM

Scientific reports 20170705 1

We report direct evidence that oxygen vacancies affect the structural and electrical parameters in tensile-strained NdNiO3-δ epitaxial thin films by elaborately adjusting the amount of oxygen deficiency (δ) with changing growth temperature T D. The modulation in tensile strain and T D tended to increase oxygen deficiency (δ) in NdNiO3-δ thin films; this process relieves tensile strain of the thin film by oxygen vacancy incorporation. The oxygen deficie ...[more]

PMID: 28680074

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