Hopping frustration-induced flat band and strange metallicity in a kagome metal

The introduction of localized electronic states into a metal can alter its physical properties, enabling exotic metal physics. This paper demonstrates transport and thermodynamic hallmarks of heavy fermion and strange metal behavior in the kagome metal Ni3In, where localized states arise from destructive interference-induced band flattening of partially filled Ni 3d states. Magnetic field and pressure tuning reveal proximity to quantum criticality, extending the analogy to f-electron Kondo lattices. These findings highlight the role of hopping frustration in generating strong correlations and suggest a lattice-driven approach to realizing correlated metals with non-trivial band topology.

Linda Ye, Shiang Fang, Mingu Kang, Josef Kaufmann, Yonghun Lee, Caolan John, Paul M. Neves, S. Y. Frank Zhao, Jonathan Denlinger, Chris Jozwiak, Aaron Bostwick, Eli Rotenberg, Efthimios Kaxiras, David C. Bell, Oleg Janson, Riccardo Comin, Joseph G. Checkelsky