论文标题
金属铁电磁磁性多铁中的eutio $ _ {3-x} $ h $ _x $
Metallic ferroelectric-ferromagnetic multiferroics in strained EuTiO$_{3-x}$H$_x$
论文作者
论文摘要
极性金属由金属性和极性晶体结构的共存来定义。它们在非线性光学元件，铁电设备和量子设备中具有潜在的应用。同时，铁电 - 铁磁性（FE-FM）多效率同时显示了铁电和铁磁学，从而导致了信息存储的新技术。对于金属性，铁电性和铁磁性是否可以在材料的单个结构域中共存，这仍然是一个悬而未决的问题。 Eutio $ _3 $正在积极研究磁性传感器，记忆，磁光设备和能量转换设备中的潜在应用。它稳定在多临界平衡处，并具有丰富的有趣特性。在这里，使用混合密度功能理论计算的结果，我们报告了hH掺杂的菌株工程外延eutio $ _3 $中的金属Fe-FM多效应。极地金属中磁性的出现为控制这些材料的应用提供了新的自由度。讨论了金属性，铁电性和铁磁性共存的基本机制。金属Eutio $ _ {3-X} $ H $ _X $中的Ferromagnetism由Ruderman-Kittel-Kasuya-Yosida（rkky）的交互作用解释，这与实验一致。金属性和铁电性的共存是因为费米水平的电子弱耦合到铁电畸变。我们的结果表明，应变和掺杂的综合效果负责实现Eutio $ _3 $ _3 $的金属Fe-FM多效应，并可能为在其他材料中获取金属Fe-FM多膜素质提供了一种新的方法。
Polar metals are defined by the coexistence of metallicity and polar crystal structure. They have potential applications in non-linear optics, ferroelectric devices, and quantum devices. Meanwhile, ferroelectric-ferromagnetic (FE-FM) multiferroics display simultaneous ferroelectricity and ferromagnetism, leading to new technologies in information storage. It remains an open question whether metallicity, ferroelectricity, and ferromagnetism can coexist in a single domain of a material. EuTiO$_3$ is actively studied for potential applications in magnetic sensors, memories, magneto-optical devices, and energy conversion devices. It stabilizes at a multi-critical equilibrium and exhibits a rich range of intriguing properties. Here, using the results from hybrid density functional theory calculations, we report metallic FE-FM multiferroics in strain-engineered epitaxial EuTiO$_3$ with H doping. The emergence of the magnetism in polar metals provides a new degree of freedom to control these materials in applications. The underlying mechanism for the coexistence of metallicity, ferroelectricity, and ferromagnetism is discussed. The ferromagnetism in metallic EuTiO$_{3-x}$H$_x$ is explained by the Ruderman-Kittel-Kasuya- Yosida (RKKY) interaction, which agrees with experiments. The coexistence of metallicity and ferroelectricity is allowed because the electrons at the Fermi level are weakly coupled to the ferroelectric distortion. Our results suggest that the combined effect of strain and doping is responsible for achieving EuTiO$_3$-based metallic FE-FM multiferroics and may provide a new way for obtaining metallic FE-FM multiferroics in other materials.
