BaDElPh Highlights

YTe₃, a nonmagnetic quasi-two-dimensional chalcogenide, exhibits an incommensurate CDW state below 334 K. Using ARPES and DFT, we establish that YTe₃ is a CDW-induced Kramers nodal line (KNL) metal, a recently proposed topological state of matter. Two mutually orthogonal CDW domains, each exhibiting a unidirectional and similar q_CDW, is revealed from both LEED and STM, while the noncentrosymmetric crystal structure has been established by x-ray crystallography and Raman spectroscopy. DFT calculated bands provides excellent agreement with ARPES when the contributions from both the twin domains are considered. The CDW gap is barely visible in the Fermi surface (FS) of YTe₃ because of the twin domains. Nevertheless, the gap could be identified by comparing with the FS measured at high temperature (345 K) in the non-CDW state. The bands calculated using DFT with SOC show a KNL along Σ resulting from the crossings between the bilayer split main and shadow bands dispersing perpendicular to the KNL.