Yu-Shiba-Rusinov states in the s-wave superconducting kagome Hubbard model: Self-consistent Bogoliubov-de Gennes calculations

Abstract

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 $J$ between such impurities and electrons. In this study, we explore a self-consistent numerical solution of the Bogoliubov-de Gennes equations for an $s$-wave superconducting kagome model with a single classical magnetic impurity. Our study reveals that with increasing $J$, 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 further increasing $J$, 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 $J$, 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.

7 pages, 4 figures

References in corpus (16)

• CsV${}_3$Sb${}_5$: a ${\mathbb{Z}}_2$ topological kagome metal with a superconducting ground state
• Roton pair density wave and unconventional strong-coupling superconductivity in a topological kagome metal
• Time-reversal symmetry-breaking charge order in a kagome superconductor
• Double superconducting dome and triple enhancement of Tc in the kagome superconductor CsV3Sb5 under high pressure
• Unusual competition of superconductivity and charge-density-wave state in a compressed topological kagome metal
• Rich Nature of Van Hove Singularities in Kagome Superconductor CsV${}_3$Sb${}_5$
• Multiband superconductivity with sign-preserving order parameter in kagome superconductor CsV3Sb5
• Doped Kagome System as Exotic Superconductor
• Study of the electronic properties of topological kagome metals YV${}_6$Sn${}_6$ and GdV${}_6$Sn${}_6$
• Microscopic evidence for anisotropic multigap superconductivity in the CsV${}_3$Sb${}_5$ kagome superconductor
• Magnetic-field induced quantum-size cascades in superconducting nanowires
• Interference-induced surface superconductivity:Enhancement by tuning the Debye energy
• Surface superconductor-insulator transition induced by an electric field
• Surface superconductor-insulator transition: Reduction of the critical electric field by Hartree-Fock potential
• Shiba states in systems with density of states singularities
• Tailoring of the interference-induced surface superconductivity by an applied electric field