Anisotropic proximity-induced superconductivity and edge supercurrent in Kagome metal, K1-xV3Sb5

Materials with Kagome nets are of particular importance for their potential combination of strong correlation, exotic magnetism, and electronic topology. KV3Sb5 was discovered to be a layered topological metal with a Kagome net of vanadium. Here, we fabricated Josephson Junctions of K1-xV3Sb5 and induced superconductivity over long junction lengths. Through magnetoresistance and current versus phase measurements, we observed a magnetic field sweeping direction-dependent magnetoresistance and an anisotropic interference pattern with a Fraunhofer pattern for in-plane magnetic field but a suppression of critical current for out-of-plane magnetic field. These results indicate an anisotropic internal magnetic field in K1-xV3Sb5 that influences the superconducting coupling in the junction, possibly giving rise to spin-triplet superconductivity. In addition, the observation of long-lived fast oscillations shows evidence of spatially localized conducting channels arising from edge states. These observations pave the way for studying unconventional superconductivity and Josephson device based on Kagome metals with electron correlation and topology.

Automated summary

Materials with Kagome nets, such as K1-xV3Sb5, show potential in exploring unconventional superconductivity and Josephson devices. In this study, Josephson junctions of K1-xV3Sb5 were fabricated, leading to the observation of magnetic field-dependent magnetoresistance and anisotropic interference patterns. An anisotropic internal magnetic field in K1-xV3Sb5 and spatially localized conducting channels arising from edge states were also observed, suggesting the presence of spin-triplet superconductivity and providing new insights for research on unconventional superconductivity and Josephson devices based on Kagome metals.