相关实验视频
Updated: May 25, 2026

08:53
Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
一种极性金刚石氧化物,在室温下表现出弱铁磁性
Man-Rong Li1, Umut Adem, Sean R C McMitchell
1Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK.
Journal of the American Chemical Society
|January 28, 2012
概括
研究人员开发了ScFeO(3) (SFO),一种多铁性材料,在室温以上具有弱铁磁性. 这一发现推动了对高温磁电材料的研究.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- 设计多铁材料需要将磁性秩序与电极性结合起来.
- 实现高温磁性秩序,特别是室温以上的磁性秩序,在多铁研究中仍然是一个重大挑战.
- 高氧化状态铁氧化物以其高磁性排序温度而闻名.
研究的目的:
- 在极性结构中合成和鉴定ScFeO (SFO) 3的特性.
- 研究SFO的磁性和结构性质,特别是其高温多铁性潜力.
- 探索SFO作为室温磁电应用的候选者.
主要方法:
- 合成的ScFeO(3) 薄膜.
- 在压力和应变下的结构特征.
- 测量磁性属性以确定排序温度和磁性状态.
主要成果:
- ScFeO(3) 在冠石结构的极性变体中得到稳定.
- 北极角金刚石ScFeO(3) 呈现出一个弱铁磁基本状态.
- 确定ScFeO(3) 的磁性排序温度低于356K,这表明室温应用的潜力.
结论:
- 极性ScFeO(3) 在室温以上表现出一个弱铁磁基态.
- 这一发现与BiFeO等类似材料的反铁磁性质形成鲜明对比.
- ScFeO ((3) 为开发新的室温磁电多铁材料提供了一个有前途的途径.
相关概念视频
Ferromagnetism
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
Diamagnetism
Materials consisting of paired electrons have zero net magnetic moments. However, when these materials are placed under an external magnetic field, the moments opposite to the field are induced. Such materials are called diamagnets. Diamagnetism is the response of the diamagnets when placed in an external magnetic field.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets.
Paramagnetism
Paramagnets are materials with unpaired electrons that possess a finite magnetic moment. In the absence of a magnetic field, these moments are randomly oriented, and thus the net moment is zero. Under an external field, a torque acting on the moments tends to align them along the field's direction. However, the random thermal motion of electrons produces a torque opposite to the external field and tries to disorient the moments. These two competing effects align only a few moments along the...
Magnetic Susceptibility and Permeability
In linear magnetic materials, like paramagnets and diamagnets, magnetization is proportional to the magnetic field intensity. The constant of proportionality, a dimensionless number, is called magnetic susceptibility. The value of the susceptibility depends on the type of material.
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
Polar Covalent Bonds
Covalent bonds are formed between two atoms when both have similar tendencies to attract electrons to themselves (i.e., when both atoms have identical or fairly similar ionization energies and electron affinities). Nonmetal atoms frequently form covalent bonds with other nonmetal atoms. For example, the hydrogen molecule, H2, contains a covalent bond between its two hydrogen atoms. When two separate hydrogen atoms with a particular potential energy approach each other, their valence orbitals...
Properties of Transition Metals
Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3–12 are transition elements. The f-block elements, also called inner transition metals (the lanthanides and actinides), also meet this criterion because the d orbital is partially occupied before the f orbitals.

