在铁弹性领域墙壁内进行反铁电式切换
Guangming Lu1, Gustau Catalan2,3, Ekhard K H Salje4
1Yantai University, School of Environmental and Materials Engineering, Yantai 264005, China.
Physical review letters
|November 30, 2025
概括
矿中的铁弹性域壁可以表现出可切换的极化,这与之前的假设相反. 分子动力学显示,高电场使这种切换成为可能,为铁弹性材料的应用提供了新的可能性.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 铁弹性材料具有可切换的自发应变,可以是中心对称的.
- 铁弹性材料中的域壁通常是极性的,这是由于柔电,由应变梯度引起的.
- 这种柔电极化通常不能通过电压切换,因为它需要域消灭.
研究的目的:
- 调查原型铁弹性矿CaTiO3中的域壁极化是否可切换.
- 为了确定可切换的偏振是否由二方位合引起,还是受到单极柔电的约束.
- 探索电场在操纵域壁属性和极化中的作用.
主要方法:
- 利用分子动力学计算来模拟电场下的铁弹性矿的行为.
- 分析了高电场对八面体倾斜和域壁特征的影响.
- 研究了极化切换机制和歇斯底里循环.
主要成果:
- 高电场抑制八面体倾斜,扩大铁弹性域壁,并诱导可切换的极化.
- 可切换的两极化发生在域墙内较低的临界电场,与大部分相比.
- 极化开关表现出一种与反铁电类似的行为,具有明显的双歇斯底里循环.
结论:
- 在铁弹性矿中,域壁极化可以切换,挑战单极柔电优势的概念.
- 观察到的切换是通过二次方程合来促进的,并且在域墙上更容易访问.
- 这些发现表明,在其他铁弹性矿中存在双歇斯底里切换的可能性,从而扩大了它们的应用范围.
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