Observation of Spin- and Charge-Density Waves on Surface of Magnetic Kagome Metal TbTi₃Bi₄

The kagome metal family offer ideal conditions to study how magnetism interacts with topological electronic bands. Recent studies have revealed intriguing electronic reconstruction due to magnetic orders of rare earth moments in titanium-based kagome antiferromagnetic LnTi₃Bi₄[1-3] (Ln = rare earth). Although various magnetic orders have been revealed by various transport and magnetometry measurements, the direct observation of the spin modulations in real space remains elusive. Herein, we report observation of single-q spin density waves (SDWs) on the surface of TbTi₃Bi₄ using spin-polarized scanning tunneling microscopy (SP-STM) [4].  Furthermore, our non-SP-STM results reveal concomitant charge density wave (CDW) in TbTi₃Bi₄. Temperature dependence studies confirm that CDW is closely associated with the SDW ordering. The SDW-driven CDW order provide new insights for understanding magnetic field modulated CDWs in Kagome antiferromagnets and other correlated magnets.

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[4] E. Cheng et al. interwoven magnetic kagome metal overcomes geometric frustration. Nat. Mater. Accepted (2025).