Abstract
The recent discovery of AV_{3}Sb_{5} (A=K,Rb,Cs) has uncovered an intriguing arena for exotic Fermi surface instabilities in a kagome metal. Among them, superconductivity is found in the vicinity of multiple van Hove singularities, exhibiting indications of unconventional pairing. We show that the sublattice interference mechanism is central to understanding the formation of superconductivity in a kagome metal. Starting from an appropriately chosen minimal tight-binding model with multiple van Hove singularities close to the Fermi level for AV_{3}Sb_{5}, we provide a random phase approximation analysis of superconducting instabilities. Nonlocal Coulomb repulsion, the sublattice profile of the van Hove bands, and the interaction strength turn out to be the crucial parameters to determine the preferred pairing symmetry. Implications for potentially topological surface states are discussed, along with a proposal for additional measurements to pin down the nature of superconductivity in AV_{3}Sb_{5}.
Highlights
The recent discovery of AV3Sb5 (A 1⁄4 K; Rb; Cs) has uncovered an intriguing arena for exotic Fermi surface instabilities in a kagome metal
We show that the sublattice interference mechanism is central to understanding the formation of superconductivity in a kagome metal
This applies to quantum magnetism, where the large geometric spin frustration inherent to the corner-sharing triangles promotes the emergence of extraordinary quantum phases [1]
Summary
Of experimental exploration is still in spin, certain tendencies about the superconducting phase are starting to crystallize. In order to retain the necessary complexity of multiple van Hove singularities in the vicinity of the Fermi level in AV3Sb5, we distill a six-band minimal model. Sublattice decoration of kagome van Hove points.—As opposed to related hexagonal van Hove singularities such as for the bipartite honeycomb lattice, the kagome bands can host two different types of van Hove singularities which we label as sublattice mixing (m type) and sublattice pure (p type), characterized by odd and even parity at the M point, respectively Employing the D6h pointgroup symmetry, our corresponding effective six-band
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
