Evidence for a Quasi-One-Dimensional Charge Density Wave in CuTe by Angle-Resolved Photoemission Spectroscopy

We report the electronic structure of CuTe with a high charge density wave (CDW) transition temperature T-c = 335 K by angle-resolved photoemission spectroscopy. An anisotropic charge density wave gap with a maximum value of 190 meV is observed in the quasi-one-dimensional band formed by Te p(x) orbitals. The CDW gap can be filled by increasing the temperature or electron doping through in situ potassium deposition. Combining the experimental results with calculated electron scattering susceptibility and phonon dispersion, we suggest that both Fermi surface nesting and electron-phonon coupling play important roles in the emergence of the CDW.