具有不同配对的韦尔超导体的对称性
Mehran Z-Abyaneh1, Mehrdad Farhoudi2, Mahdi Mashkoori3,4
1Department of Physics, Shahid Beheshti University, 1983969411, Tehran, Iran. me_zahiri@sbu.ac.ir.
Scientific reports
|April 21, 2025
概括
在时间逆向对称性被打破的韦尔超导体中,富尔德-费雷尔-拉金-奥夫奇尼科夫配对只打破了U(1) 尺度对称性,与巴丁-库珀-施里弗配对不同. 这导致了一个新兴的伪尺度相位模式和一个伪Meissner效应.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子材料是一种量子材料.
- 超导电性 超导电性 超导电性
背景情况:
- 研究拓超导体的对称性质对于理解它们的奇特现象至关重要.
- 维尔超导体是拓超导体的一类,由于时间逆向对称被打破,因此具有独特的电子特性.
研究的目的:
- 分析博戈利乌博夫-德·金纳斯哈密尔顿式及其对称性在3D维尔超导体中,时间逆向对称性被打破.
- 为了比较不同配对类型 (Bardeen-Cooper-Schrieffer与Fulde-Ferrell-Larkin-Ovchinnikov) 的对称性破坏效应.
主要方法:
- 对博戈卢布洛夫-德热内斯汉密尔顿人的分析.
- 在消失配对潜力的极限上进行对称性分析.
- 研究不同配对机制下的自发对称性破坏.
主要成果:
- 当配对潜力消失时,哈密尔顿式表现出U(1) 标尺和轴对称.
- 巴丁 - 库珀 - 施里弗配对打破了U(1) 和轴对称.
- 富尔德-费雷尔-拉尔金-奥夫奇尼科夫配对仅打破了U(1) 标尺对称性,该对称性通过标量相模式恢复.
结论:
- 需要两种Nambu-Goldstone模式来恢复被巴丁-库珀-施里弗配对破坏的对称性.
- 从Fulde-Ferrell-Larkin-Ovchinnikov配对中产生了一个新兴的伪尺度相模式.
- 这种伪尺度相位模式在韦尔超导体中产生伪迈斯纳效应.
相关概念视频
01:28Types Of Superconductors
880
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...
880
01:28Symmetry in Maxwell's Equations
3.2K
Once the fields have been calculated using Maxwell's four equations, the Lorentz force equation gives the force that the fields exert on a charged particle moving with a certain velocity. The Lorentz force equation combines the force of the electric field and of the magnetic field on the moving charge. Maxwell's equations and the Lorentz force law together encompass all the laws of electricity and magnetism. The symmetry that Maxwell introduced into his mathematical framework may not be...
3.2K
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
910
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
910
01:07Symmetric Member in Bending
164
In the study of the mechanics of materials, analyzing the behavior of prismatic members under opposing couples is crucial for understanding internal stress distributions, which are essential for structural design. When subjected to couples, a prismatic member experiences internal forces that maintain equilibrium. A couple, characterized by two equal and opposite forces, creates a moment but no resultant force. The internal forces at any section cut of the member must balance these external...
164
01:08Spin–Spin Coupling Constant: Overview
846
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
846
01:17Spin–Spin Coupling: One-Bond Coupling
908
Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
908