反鉄磁石の電気スイッチング

P Wadley¹, B Howells², J Železný³

¹School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK. peter.wadley@nottingham.ac.uk.

Science (New York, N.Y.)

|February 4, 2016

まとめ

研究者らは,電流誘発フィールドを用いた反鉄磁気装置の室温電気スイッチングを実証した. 高密度スピントロニックメモリ技術の開発に新たな道を開きます

科学分野:

凝縮物質物理学
材料科学
量子力学

背景:

アンチフェロマグネットは交互の磁気モメントを有し,その結果,純磁化がゼロになり,外部磁場で操作するのが困難になります.
相対論的量子力学は,反鉄磁石の中で電流誘導された内部フィールドを生成するための経路を提供します.

研究の目的:

室温での反鉄磁気薄膜装置の安定した構成の間の電気的な切り替えを実証する.
先進的なスピントロニックアプリケーションのための反鉄磁石の潜在能力を探求する.

主な方法:

反鉄磁気格子周期性で交替する電流誘発の内部フィールドを使用した.
反鉄磁性CuMnA薄膜装置を使用しています.
10^6 A/cm^2の大きさの電流をスイッチングに使用する.

主要な成果:

CuMnAs薄膜装置で安定した磁気構成間の室温電気スイッチングを達成しました.
ソリッドステートメモリ装置内での電気的な書き込みと読み取りの能力を実証した.
磁気状態は磁場外からの干渉に無反応だ

結論:

アンチフェロマグネットは,電流誘発フィールドを使用して効果的に制御し,外部磁場操作の制限を克服することができます.
証明された電気的なスイッチングと固有の堅固さは,将来のスピントロニックメモリデバイスにとって非常に有望なアンチフェロマグネットを可能にします.
この研究は,次世代,高密度,安定したメモリ技術の開発における反鉄磁性材料のユニークな利点を強調しています.

さらに関連する動画

12:20

Sputter Growth and Characterization of Metamagnetic B2-ordered FeRh Epilayers

Published on: October 5, 2013

15.1K

08:25

Chemical Vapor Deposition of an Organic Magnet, Vanadium Tetracyanoethylene

Published on: July 3, 2015

12.1K

関連する概念動画

01:31

Ferromagnetism

3.5K

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...

3.5K

01:27

Magnetic Fields

7.8K

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...

7.8K

01:30

Paramagnetism

3.2K

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...

3.2K

01:24

Potential Due to a Magnetized Object

857

Magnetic dipoles in magnetic materials are aligned when placed under an external magnetic field. For paramagnets and ferromagnets, dipole alignment occurs in the direction of the magnetic field. However, the dipoles align opposite to the field in the case of diamagnets. This state of magnetic polarization due to the external field is called magnetization. Magnetization is defined as the dipole moment per unit volume. It plays a similar role to polarization in electrostatics.
The vector...

857

01:26

Diamagnetism

3.4K

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....

3.4K

01:28

Magnetostatic Boundary Conditions

1.8K

An electric field suffers a discontinuity at a surface charge. Similarly, a magnetic field is discontinuous at a surface current. The perpendicular component of a magnetic field is continuous across the interface of two magnetic mediums. In contrast, its parallel component, perpendicular to the current, is discontinuous by the amount equal to the product of the vacuum permeability and the surface current. Like the scalar potential in electrostatics, the vector potential is also continuous...