新しい層の鉄アルセニド超伝導体: (Ca,Pr) FeAs2
Hiroyuki Yakita1, Hiraku Ogino, Tomoyuki Okada
1Department of Applied Chemistry, The University of Tokyo , 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|January 7, 2014
まとめ
鉄基の超伝導体 (Ca,Pr) FeAs2という新しい超伝導体が発見され,その超伝導性は約20Kで観測されました.この新しい材料は,将来の超伝導応用の可能性のあるユニークな結晶構造を示しています.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 固体化学 固体化学
背景:
- 超伝導性は,特定の材料で観察される量子力学的現象であり,損失のない電流を可能にします.
- 鉄基超伝導体は,超伝導性を発揮する重要な材料のクラスであり,技術的進歩の可能性を秘めています.
研究 の 目的:
- (Ca,Pr) FeAs2.2.として表記された新しい鉄基超伝導体の発見を報告するために.
- 新しく発見されたこの相の結晶構造と超伝導性特性を特徴づける.
主な方法:
- 単結晶X線微分分析を用いて結晶構造を決定した.
- 超伝導体の振る舞いを評価するために,磁気化と抵抗性の測定が行われました.
主要な成果:
- 新しいフェーズである (Ca,Pr) FeAs2は,板状の結晶形式で成功して合成されました.
- 結晶構造は,空間群P21/mのモノクリニックで,Ca(Pr) 平面,Fe2As2層,As2ジグザグ状の鎖を特徴としている.
- 超伝導性は,約20Kの臨界温度 (T (c)) で確認されました.
結論:
- (Ca,Pr) FeAs2の発見は,鉄基超伝導体の家族を拡大する.
- 独特の結晶構造と観測された超伝導性は,この物質システムに関するさらなる研究の可能性を強調しています.
関連する概念動画
Types 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
Ferromagnetism
2.8K
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...
2.8K
Superconductor
1.9K
A substance that reaches superconductivity, a state in which magnetic fields cannot penetrate, and there is no electrical resistance, is referred to as a superconductor. In 1911, Heike Kamerlingh Onnes of Leiden University, a Dutch physicist, observed a relation between the temperature and the resistance of the element mercury. The mercury sample was then cooled in liquid helium to study the linear dependence of resistance on temperature. It was observed that, as the temperature decreased, the...
1.9K
Theory of Metallic Conduction
2.0K
The conduction of free electrons inside a conductor is best described by quantum mechanics. However, a classical model makes predictions close to the results of quantum mechanics. It is called the theory of metallic conduction.
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
2.0K
Metallic Solids
16.4K
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and...
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and...
16.4K
Paramagnetism
2.4K
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...
2.4K


