Multiferroic nature of intrinsic point defects in BiFeO3: A hybrid Hartree-Fock density functional study
Multiferroic nature of intrinsic point defects in BiFeO3: A hybrid Hartree-Fock density functional study
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BiFeO3 中本征点缺陷的多铁性质：混合 Hartree-Fock 密度泛函研究
DOI：
10.1103/physrevb.93.174107
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发表时间：
2016
影响因子：
3.7
通讯作者：
Kitamura Takayuki
中科院分区：
文献类型：
--
作者：
Shimada Takahiro;Matsui Takahiro;Xu Tao;Arisue Kou;Zhang Yajun;Wang Jie;Kitamura Takayuki
为了从根本上理解中本征空位的多铁性行为和电子性质，我们基于混合Hartree-Fock密度泛函理论进行了第一性原理计算，该理论可以准确地描述缺陷电子结构。氧空位，这表现为深施主与高浓度的贫氧条件下，减少在中性状态下相邻的Fe离子的磁矩，而带电的氧空位诱导额外的铁电极化。另一方面，阳离子空位可能在富氧条件下形成，并导致与氧空位诱导的多铁性不同的多铁性。Bi空位作为三重浅受体，强烈抑制自发极化，而Fe空位局部干扰电和自旋极化，因此被视为多铁性奇点。从缺陷态的定域/离域特征可以系统地理解空位的多种多样的多铁性行为，而空位的不同形成条件提供了通过控制空位的浓度和电荷态来定制空位的多铁性的策略.
To achieve a fundamental understanding of the multiferroic behavior and electronic properties of intrinsic vacancies in, here we performed first-principles calculations based on hybrid Hartree-Fock density functional theories, which can accurately describe defect electronic structures. Oxygen vacancies, which behave as deep donors with high concentrations under oxygen-poor conditions, reduce the magnetic moments at neighboring Fe ions in the neutral state, while charged oxygen vacancies induce additional ferroelectric polarizations. Cation vacancies, on the other hand, are likely to form under oxygen-rich conditions and result in multiferroic properties distinct from those induced by oxygen vacancies. Bi vacancies act as triple-shallow acceptors and strongly suppress spontaneous polarization regardless of charge states, while Fe vacancies locally interfere with both electric and spin polarization and are thus regarded as multiferroic singular points in. A rich variety of the multiferroic behavior of vacancies can be systematically understood from the localized/delocalized features of defect states, and the different formation conditions for vacancies provide a strategy to tailor the multiferroic properties ofthrough control of the concentration and charge states of vacancies.