関連する実験動画
Updated: Apr 19, 2026

12:20
Sputter Growth and Characterization of Metamagnetic B2-ordered FeRh Epilayers
Published on: October 5, 2013
15.2K
電場を用いた室温でのフェロマグネティズムを決定的に切り替える
1Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA.
Nature
|December 19, 2014
まとめ
研究者は,BiFeO3.3で室温で電場による磁力の制御を実証しました. マルチフェロイクスのこの突破は,Dzyaloshinskii-Moriyaベクトルの決定的なスイッチングを可能にし,エネルギー効率の良い電子機器への道を開く.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
- ナノテクノロジー ナノテクノロジー
背景:
- マルチフェロ材料は,電場による磁力の制御を提供しており,これはデバイスのアプリケーションに不可欠です.
- ビスムートフェライト (BiFeO3) は,室温磁電結合を持つ唯一の単相マルチフェロイックです.
- その磁性は,Dzyaloshinskii-Moriya (DM) 相互作用から生じ,以前の理論はDMベクトルの直接的偏振スイッチングを禁止していた.
研究 の 目的:
- BiFeO3.3におけるスイッチングプロセスの運動学を調査する.
- DMベクトルの決定的電場制御と室温での磁化を実証する.
- 装置におけるエネルギー効率の高い磁電スイッチングの可能性を調査する.
主な方法:
- スイッチング運動を分析するための第一原理計算.
- 決定的な磁気化の逆転の実験的観測.
- 観察されたスイッチングメカニズムを使用して,スピンバルブ装置の制御の実証.
主要な成果:
- 動力学によって支配される2段階のスイッチングプロセスを特定し,DMベクトルと傾斜モメントの決定的反転を可能にしました.
- 室温の電気場を使用して磁気化の180度決定的切り替えを達成しました.
- スピンバルブ装置のエネルギー効率の良い制御が実証され,スピントランスファートルクスイッチングよりもはるかに少ないエネルギーを必要とします.
結論:
- 基本状態の対称性だけでなく,スイッチングの運動学も,BiFeO3.3における決定的磁電スイッチングを理解し,達成するための鍵です.
- この研究は,低エネルギー,非揮発性ナノメートルスケールの電子機器のための磁電スイッチングのエンジニアリングのための経路を提供します.
- この発見は,将来のマルチフェロイドおよび磁電装置の設計に大きく影響する.
関連する概念動画
Ferromagnetism
3.6K
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...
3.6K
Magnetic Fields
8.1K
A moving charge or a current creates a magnetic field in the surrounding space, in addition to its electric field. The magnetic field exerts a force on any other moving charge or current that is present in the field. Like an electric field, the magnetic field is also a vector field. At any position, the direction of the magnetic field is defined as the direction in which the north pole of a compass needle points.
A magnetic field is defined by the force that a charged particle experiences...
A magnetic field is defined by the force that a charged particle experiences...
8.1K
Paramagnetism
3.3K
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...
3.3K
Diamagnetism
3.6K
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....
3.6K
Types Of Superconductors
1.9K
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...
1.9K
Induced Electric Fields: Applications
3.0K
An important distinction exists between the electric field induced by a changing magnetic field and the electrostatic field produced by a fixed charge distribution. Specifically, the induced electric field is nonconservative because it does not work in moving a charge over a closed path. In contrast, the electrostatic field is conservative and does no net work over a closed path. Hence, electric potential can be associated with the electrostatic field but not the induced field. The following...
3.0K

