Flat bands for strange metals and correlated topology

by Qimiao Si (Rice University, Houston TX)

Monday 10 Jun 2024, 11:00 → 12:00 Europe/Zurich

WGBG/019

The field of correlation physics continuously expands its horizons. Metals with active flat bands have been of considerable interest in recent years. In addition to moire structures, frustrated lattice systems with a destructive kinematic interference provide a rich platform for realizing novel phases, including the interplay between correlation and electronic topology.

In this talk, I will discuss flat bands in correlated d-electron-based frustrated lattice systems [1,2,3]. The notion of compact molecular orbitals is introduced [3], which leads to a Kondo lattice description [1]. This allows us to advance the first theoretical understanding of the strange metallicity observed in frustrated-lattice metals, and predict a phase diagram that has been supported by recent experiments in a new kagome metal. We also show that such d-electron-based systems serve as a new platform for realizing Weyl-Kondo semimetals [2]. I’ll discuss some general implications of the work, including the notion that strange metallicity amplifies quantum entanglement [4].

 [1] H. Hu and Q. Si, Sci. Adv. 9, eadg0028 (2023).

[2] L. Chen et al., arXiv:2212.08017 (Nat Comm, in press).

[3] L. Chen et al., arXiv:2307.09431

[4] Y. Fang et al., arXiv:2402.18552.