全酸化基の合成アンチフェロマグネット,層分解磁化逆転を示す
Binbin Chen1,2, Haoran Xu1, Chao Ma1
1Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei 230026, China.
Science (New York, N.Y.)
|July 15, 2017
まとめ
研究者らは,超薄な鉄磁性酸化物層で反鉄磁性層間交換結合 (AF-IEC) を設計した. この突破は,先進的な電子機器のための新しい酸化物インターフェイスで制御された磁気スイッチングを可能にします.
科学分野:
- 材料科学
- 凝縮物質物理学
- オキシードエレクトロニクス
背景:
- ナノスケールの磁石層の劣化による反鉄磁石と相関する酸化物を合成することは困難である.
- オキシードインターフェイスで制御された磁気結合を達成することは,次世代の電子機器にとって極めて重要です.
研究 の 目的:
- 超薄の鉄磁性酸化物層間の反鉄磁性層間交換結合 (AF-IEC) を設計する.
- 層別解像度の磁気スイッチと制御可能なヒステリシスループを実証する.
- キュリー温度の高い代替磁気材料の使用を検討する.
主な方法:
- 超薄な鉄磁石のLa2/3Ca1/3MnO3層を隔離するCaRu1/2Ti1/2O3隔離器で分離したヘテロ構造の製造.
- 層解析磁気スイッチング測定を用いた磁気特性の調査.
- ヒステレスループと磁気化高原の特徴
主要な成果:
- 超薄なLa2/3Ca1/3MnO3層の間のAF-IECの成功エンジニアリング
- 二層重複に依存する磁気化高地を持つ鋭い,ステップ型のヒステレスループの観測.
- 適度な磁場での磁気スイッチングの実証 (オーステッド数百).
- 室温に近いキュリー温度を持つ材料であるLa2/3Sr1/3MnO3を用いたAF-IECの実現.
結論:
- 設計されたAF-IECは,酸化物ヘテロ構造における磁性を制御するための経路を提供します.
- 観察された層分解磁性スイッチングと鋭いヒステレスループは,酸化物ベースのデバイスに新しい機能を提供します.
- この研究は,相関性オキシドを高度な電子アプリケーションで利用する可能性を広げています.
関連する概念動画
01:31Ferromagnetism
3.2K
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...
3.2K
01:05Atomic Nuclei: Magnetic Resonance
1.3K
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
1.3K
03:02Colors and Magnetism
14.3K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
14.3K
01:26Diamagnetism
3.1K
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....
3.1K
01:28Types Of Superconductors
1.7K
A superconductor is a substance that offers zero resistance to the electric current when it drops below a critical temperature. Zero resistance is not the only interesting phenomenon as materials reach their transition temperatures. A second effect is the exclusion of magnetic fields. This is known as the Meissner effect. A light, permanent magnet placed over a superconducting sample will levitate in a stable position above the superconductor. High-speed trains that levitate on strong...
1.7K
01:31Magnetic Susceptibility and Permeability
2.5K
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...
2.5K