Violation of Pauli-Clogston limit in the heavy-fermion superconductor CeRh2As2: Duality of itinerant and localized 4 f electrons
Violation of Pauli-Clogston limit in the heavy-fermion superconductor CeRh2As2: Duality of itinerant and localized 4 f electrons
复制标题
重费米子超导体 CeRh2As2 违反泡利-克洛斯顿极限：巡回电子和局域 4 f 电子的对偶性
DOI：
10.1103/physrevb.106.184509
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Kazushige Machida
中科院分区：
文献类型：
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作者：
Mikito Koga;Masashige Matsumoto;Kazushige Machida
本文从自旋单重态配对的观点出发，从理论上提出了一种机制来解释含Ce重费米子材料中所观测到的上临界场的Pauli-Clogston极限的破坏。它是基于一个对偶概念，一个电子的双重同时方面：准粒子（QP）的巡回部分和局域部分起源于Ce原子的4f电子。当巡游量子点直接参与形成库珀对时，局域量子点通过它们之间的反铁磁交换作用施加内场以对抗外加场。这通常是密集近藤晶格系统所固有的。我们认为，这种机制不仅适用于局部非中心对称材料，而且适用于全局反演对称破缺的Ce基材料，如。此外，我们指出，它也适用于强违反Pauli极限的自旋三重态配对系统，如。
We theoretically propose a mechanism to understand the violation of the Pauli-Clogston limit for the upper critical fieldobserved in the Ce bearing heavy Fermion materialfrom the view point of spin singlet pairing. It is based on a duality concept, the dual simultaneous aspects of an electron: The itinerant part and localized part of quasiparticles (QPs) originated from the 4felectrons of the Ce atoms. While the itinerant QPs directly participate in forming the Cooper pairs, the localized QPs exert the internal field so as to oppose the applied field through the antiferromagnetic exchange interaction between them. This is inherent in the dense Kondo lattice system in general. We argue that this mechanism can be applied not only to the locally noncentrosymmetric material, but also to globally inversion symmetry broken Ce-based materials such as. Moreover, we point out that it also works for strongly Pauli-limit-violated spin triplet pairing systems, such as.