Evidence for quasi-one-dimensional charge density wave in CuTe by angle-resolved photoemission spectroscopy

TL;DR

This study uses ARPES to reveal a high-temperature quasi-one-dimensional charge density wave in CuTe, showing how Fermi surface nesting and electron-phonon interactions contribute to its formation.

Contribution

It provides the first detailed ARPES analysis of CuTe's electronic structure and elucidates the mechanisms behind its high-temperature CDW transition.

Findings

Observation of a 190 meV anisotropic CDW gap in CuTe

Temperature and doping can fill the CDW gap

Both Fermi surface nesting and electron-phonon coupling are key to CDW emergence

Abstract

We report the electronic structure of CuTe with a high charge density wave (CDW) transition temperature Tc = 335 K by angle-resolved photoemission spectroscopy (ARPES). An anisotropic charge density wave gap with a maximum value of 190 meV is observed in the quasi-one-dimensional band formed by Te px orbitals. The CDW gap can be filled by increasing 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.