Pressure tuning of electronic correlations and flat bands in
Phys. Rev. B 114, 055124 – Published 20 July, 2026
DOI: https://doi.org/10.1103/pqbc-87xb
Abstract
is a newly identified strongly correlated kagome superconductor, characterized by non-Fermi-liquid behavior at elevated temperatures and intertwined charge and spin density wave order below . Under external pressure, this order is suppressed and a superconducting phase emerges. This phase diagram, which closely resembles that of high- superconductors, together with a kagome flat band near the Fermi level and possible altermagnetic order, has motivated extensive theoretical and experimental investigations. To better understand how pressure influences the ordered states, we present a systematic study of the evolution of the electronic properties under applied pressure. Performing density functional theory combined with dynamical mean field theory calculations, we uncover a complex interplay between the redistribution of spectral weight in the flat bands and the strength of electronic correlations under pressure. Our results further strengthen the interpretation that pressure effectively weakens electronic correlations through enhanced orbital hybridization. This, in turn, strongly suggests that superconductivity emerges as a direct consequence of the suppression of the system's ordered phase.