Emergent phenomena in kagome thin films: a spectroscopic perspective

Abstract Kagome materials have recently emerged as a versatile platform for exploring the intricate interplay among lattice, charge, spin, and orbital degrees of freedom, giving rise to a rich variety of quantum phenomena. While early studies predominantly focused on bulk kagome crystals, recent efforts have increasingly shifted toward their thin-film counterparts, motivated by the pursuit of enhanced tunability and potential device integration. Compared to bulk crystals, thin films offer distinct advantages such as precise control over strain, substrate-induced interactions, and reduced dimensionality, which together enable the modulation of electronic structures and the stabilization of emergent states. In particular, the ability to fine-tune key band features relative to the Fermi level provides a powerful route for engineering exotic states, including flat-band-driven magnetism, topological phases, and correlated electron phenomena. In this review, we provide a comprehensive overview of recent advances in the synthesis, characterization, and electronic structure studies of kagome thin films. We highlight key experimental breakthroughs that reveal how their topological and correlated properties evolve and discuss their broader significance within the landscape of quantum materials. Given the rapid convergence of experimental observations across diverse kagome systems, this review aims to offer timely guidance for future efforts toward unraveling the microscopic mechanisms of these unconventional electronic states.