Analysis of the spectral function of Nd_(1.85)Ce_(0.15)CuO_4 obtained by angle-resolved photoemission spectroscopy

摘要

Samples of Nd_(2-x)Ce_xCuO_4, an electron-doped high-temperature superconducting cuprate, near optimal doping at x=0.155 were measured via angle-resolved photoemission. We report a renormalization feature in the self-energy ("kink") in the band dispersion at ≈50-60 meV present in nodal and antinodal cuts across the Fermi surface. Specifically, while the kink had been seen in the antinodal region, it is now observed also in the nodal region, reminiscent of what has been observed in hole-doped cuprates.