We report a high-resolution angle-resolved photoemission spectroscopic study of the electron-doped ( $n$-type) cuprate superconductor ${\mathrm{Nd}}_{1.85}{\mathrm{Ce}}_{0.15}{\mathrm{CuO}}_4$. We observe regions along the Fermi surface where the near- $E_F$ intensity is suppressed and the spectral features are broad in a manner reminiscent of the high-energy “pseudogap” in the underdoped $p$-type (hole doped) cuprates. However, instead of occurring near the $(\pi ,0\mathrm{})$ region, as in the $p$-type materials, this pseudogap falls near the intersection of the underlying Fermi surface with the antiferromagnetic Brillouin zone boundary.

• Received 21 December 2000

DOI:https://doi.org/10.1103/PhysRevLett.87.147003