Convert Widespread Paraelectric Perovskite to Ferroelectrics
Convert Widespread Paraelectric Perovskite to Ferroelectrics
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将广泛使用的顺电钙钛矿转化为铁电材料
DOI：
10.1103/physrevlett.128.197601
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发表时间：
2022
影响因子：
8.6
通讯作者：
Wu, Xifan
中科院分区：
文献类型：
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作者：
Wang, Hongwei;Tang, Fujie;Stengel, Massimiliano;Xiang, Hongjun;An, Qi;Low, Tony;Wu, Xifan
虽然自然界提供了大量的钙钛矿材料，但只有少数材料表现出很大的铁电性，可能还具有多铁性。钙钛矿材料大多为非极化结构，限制了其应用范围。基于有效哈密顿模型和第一性原理计算，我们提出了一种稳定功能型结构的通用薄膜设计方法，这种结构是广泛存在于CTO型钙钛矿氧化物中的一种常见亚稳态结构。研究发现，CTO型钙钛矿中的反铁电性和BFO型钙钛矿中的铁电性与力学和电学边界条件有明显的依赖关系，这两个边界条件都涉及氧的八面体旋转和倾斜。上述差异可用于稳定许多CTO型钙钛矿材料中的高极性BFO型结构。
While nature provides a plethora of perovskite materials, only a few exhibit large ferroelectricity and possibly multiferroicity. The majority of perovskite materials have the nonpolarstructure, limiting the scope of their applications. Based on the effective Hamiltonian model as well as first-principles calculations, we propose a general thin-film design method to stabilize the functional-type structure, which is a common metastable structure in widespread CTO-type perovskite oxides. It is found that the improper antiferroelectricity in CTO-type perovskite and ferroelectricity in BFO-type perovskite have distinct dependences on mechanical and electric boundary conditions, both of which involve oxygen octahedral rotation and tilt. The above difference can be used to stabilize the highly polar BFO-type structure in many CTO-type perovskite materials.