基于第一原则的蒙特卡洛模型对缺氧的Fe替代SrTiO3的磁化进行了建模
Juan M Florez1, Miguel A Solis1, Emilio A Cortés Estay1
1Grupo de Simulaciones, Departamento de Física, Universidad Técnica Federico Santa María, Valparaíso, 2390123, Chile. juanmanuel.florez@usm.cl.
Physical chemistry chemical physics : PCCP
|July 11, 2023
概括
铁替代的酸 (SrTi$_{1-x}$Fe$__x$O$_{3-\delta}$) 中的氧气空隙可以增强磁化. 这项研究揭示了最大磁性质的最佳空隙度,这对于调材料性能至关重要.
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:
- 过渡金属 (TM) 替代的SrTiO$_{3}$通过缺陷和兴奋剂表现出可调节的磁性和铁电.
- 铁替代的酸 (SrTi$_{1-x}$Fe$_x$O$_{3-\delta}$,STF) 显示出对磁性应用的前景,具有对合成条件敏感的特性.
研究的目的:
- 研究氧气空缺 (V$_{O}$) 状态和度对STF磁化的影响.
- 在STF中建立氧气空置工程和磁性行为之间的关系.
主要方法:
- 利用混合密度函数理论 (DFT) 来建模V$_{O}$对Fecation安排的影响.
- 采用蒙特卡洛模型来对准线性磁力学,并结合了DFT计算的磁性状态.
- 模拟自发磁化作为氧空位度的函数.
主要成果:
- 该模型准确地复制了STF磁化中的实验趋势.
- 磁化随着空缺度小而增加,达到每配方单位约0.35 $\mu$B的峰值.
- 磁化逐渐减少,随着空位度的进一步增加.
结论:
- 氧气空缺工程是控制STF磁化的一个关键因素.
- 该研究提供了对优化氧空位度以获得最大磁性性能的见解.
- 结果将空位度与强化磁化所需的氧气压力相关联.
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