Twist-Induced Quantum Geometry Reconfiguration in Moiré Flat Bands

The interplay between band topology, Berry curvature, and moiré flat bands lies at the heart of recent advances in quantum materials. In well-studied moiré systems such as twisted bilayer graphene and transition metal dichalcogenides, the quantum geometry of moiré flat bands typically reflects that of the monolayer, with Berry curvature originating from the band edge at the same valley. Whether this correspondence persists in systems with complex monolayer band structures and broken symmetries remains unclear. Here, we study twisted bilayers of loop-current-ordered kagome lattices (tb-LCK), which have been proposed in the context of vanadium-based kagome materials, using tight-binding models, and uncover a twist-induced reconfiguration of quantum geometry. By tuning the phase of the loop-current order, we identify the suppression of monolayer Berry curvature through twist-driven band reconstruction. We attribute these effects to strong interlayer hybridizations, enabled by the unusually large interlayer tunneling inherent to vanadium-based kagome materials, which mix energetically distant states and reshape quantum geometry. These results reveal that twist in tb-LCK suppresses quantum geometric inheritance from the monolayer, and establish loop-current-ordered moiré systems as promising platforms for exploring unconventional quantum geometry in moiré flat bands. We further comment on the experimental feasibility of the proposed system via vanadium-based kagome materials.

Recommended citation: Yi-Chun Hung, Xiaoting Zhou, and Arun Bansil. Twist-Induced Quantum Geometry Reconfiguration in Moiré Flat Bands arXiv:2603.20849.
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