Ding Shuaibo, Bai Yunfei, Bulekov A A, Zhang Wenhui, Shanenko A A, Chen Yajiang
Zhejiang Key Laboratory of Quantum State Control and Optical Field Manipulation, Department of Physics, Zhejiang Sci-Tech University, 310018 Hangzhou, China.
HSE University, 101000 Moscow, Russia.
J Phys Chem Lett. 2024 Sep 5;15(35):9084-9091. doi: 10.1021/acs.jpclett.4c02322. Epub 2024 Aug 28.
Significant research has recently been conducted into the Yu-Shiba-Rusinov (YSR) states in kagome superconductors through theoretical modeling and experimental investigations. However, additional efforts are still needed to further understand the local superconductivity near magnetic impurities in the kagome lattice and clarify how relevant quantities depend on the interaction strength, , between such impurities and electrons. In this study, we explore a self-consistent numerical solution of the Bogoliubov-de Gennes equations for an -wave superconducting Kagome model with a single classical magnetic impurity. Our study reveals that with increasing , the local pair potential is systematically depressed in the vicinity of the impurity, similar to previous results obtained for the square and triangular lattices. Moreover, when is further increased, the system undergoes a first-order phase transition with the appearance of stable and metastable states, reflecting the presence of the hysteresis loop in the pertinent quantities. As a consequence of this transition, the minimal energy of the stable YSR state is nonzero at any , contrary to the expectations based on the assumption of a constant pair potential. A distinctive feature of the kagome lattice is that characteristics of the first-order transition are very sensitive to the position of the chemical potential within the kagome energy spectrum.
最近通过理论建模和实验研究对 Kagome 超导体中的汤川-芝-拉西诺夫(YSR)态进行了大量研究。然而,仍需要进一步努力来深入了解 Kagome 晶格中磁性杂质附近的局域超导性,并阐明相关量如何依赖于此类杂质与电子之间的相互作用强度 。在本研究中,我们探索了具有单个经典磁性杂质的 s 波超导 Kagome 模型的 Bogoliubov-de Gennes 方程的自洽数值解。我们的研究表明,随着 的增加,杂质附近的局域对势会系统性地降低,这与之前在正方形和三角形晶格中得到的结果类似。此外,当 进一步增加时,系统会经历一级相变,出现稳定态和亚稳态,这反映了相关量中存在滞后回线。作为这种相变的结果,稳定 YSR 态的最小能量在任何 时都不为零,这与基于恒定对势假设的预期相反。Kagome 晶格的一个显著特征是一级相变的特性对 Kagome 能谱内化学势的位置非常敏感。