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Kagome lattices have emerged as an ideal platform for exploring exotic quantum phenomena in materials. Here, we report the discovery of Ti-based kagome metal YbTi3Bi4 which we characterize using angle-resolved photoemission spectroscopy (ARPES) and magneto-transport, in combination with density functional theory calculations. Our ARPES results reveal the complex fermiology of YbTi3Bi4 and provide spectroscopic evidence of four flat bands. Our measurements also show the presence of multiple van Hove singularities originating from Ti 3d orbitals and a linearly-dispersing gapped Dirac-like bulk state at the point in accord with our theoretical calculations. Our study establishes YbTi3Bi4 as a platform for exploring exotic phases in the wider LnTi3Bi4 (Ln = lanthanide) family of materials. 

Abstract Charge density wave (CDW) ordering has been an important topic of study for a long time owing to its connection with other exotic phases such as superconductivity and magnetism. The$$R{\textrm{Te}}_{3}$$ $R{\text{Te}}_3$(R= rare-earth elements) family of materials provides a fertile ground to study the dynamics of CDW in van der Waals layered materials, and the presence of magnetism in these materials allows to explore the interplay among CDW and long range magnetic ordering. Here, we have carried out a high-resolution angle-resolved photoemission spectroscopy (ARPES) study of a CDW material$${\textrm{Gd}}{\textrm{Te}}_{3}$$ $\text{Gd}{\text{Te}}_3$, which is antiferromagnetic below$$\sim \mathrm {12~K}$$ $\sim 12K$, along with thermodynamic, electrical transport, magnetic, and Raman measurements. Our ARPES data show a two-fold symmetric Fermi surface with both gapped and ungapped regions indicative of the partial nesting. The gap is momentum dependent, maximum along$${\overline{\Gamma }}-\mathrm{\overline{Z}}$$ $\overline{\Gamma }-\overline{Z}$and gradually decreases going towards$${\overline{\Gamma }}-\mathrm{\overline{X}}$$ $\overline{\Gamma }-\overline{X}$. Our study provides a platform to study the dynamics of CDW and its interaction with other physical orders in two- and three-dimensions.