Versatile multi-q antiferromagnetic charge order in correlated vdW metals

TL;DR

This study uncovers multiple competing electronic states in the vdW metal CeTe3, revealing tunable antiferromagnetic charge order and complex many-body interactions driven by magnetic fields and correlations.

Contribution

It demonstrates the existence of versatile, tunable antiferromagnetic charge-ordered states in CeTe3, a correlated vdW metal, expanding understanding of quantum phases in 2D materials.

Findings

Multiple charge-ordered antiferromagnetic phases identified

Magnetic field modulates competition between electronic states

Broad electronic reconstruction extends to ~30 meV from EF

Abstract

Following the discovery of graphene, interest in van der Waals (vdW) materials has surged; however, advancing physics beyond graphene requires quantum vdW materials platforms that host versatile, strongly interacting many-body states. Here, using scanning tunneling microscopy and spectroscopy at 300 mK, we uncover multiple competing electronic states in the van der Waals metal CeTe3: charge-ordered antiferromagnetic phases forming stripe and checkerboard orders. Remarkably, their competition is tuned by a modest in-plane magnetic field (~1.5 T), revealing strongly intertwined multiple frustrations involving antiferromagnetism, charge order, and Fermi-surface instabilities. Quasiparticle-interference imaging directly identifies the momentum-space origin of these competitions on the representative semimetals Fermi surface. While the observations can be understood at a basic level in terms of Kondo coupling between localized Ce 4f moments and itinerant Te 5p electrons, our results reveal a much richer phenomenology: an unusually broad electronic reconstruction extending to an energy scale of roughly 30 meV from EF, which realizes and deforms antiferromagnetic charge-ordered states and signals strongly correlated interactions beyond a weak-coupling description. Beyond establishing CeTe3 as a model platform, our results demonstrate that competing instabilities in antiferromagnetic two-dimensional metals/semimetals generate versatile electronic phases, opening a route to tunable nanoscale quantum states governed by the intertwined effects of correlation, symmetry, and topology.