title: Doping dependence of an n-type cuprate superconductor investigated by angle-resolved photoemission spectroscopy.
abstract: We present an angle-resolved photoemission doping dependence study of the n-type cuprate superconductor Nd(2-x)Ce(x)CuO(4+/-delta), from the half-filled Mott insulator to the T(c) = 24 K superconductor. In Nd2CuO4, we reveal the charge-transfer band for the first time. As electrons are doped into the system, this feature's intensity decreases with the concomitant formation of near- E(F) spectral weight. At low doping, the Fermi surface is an electron-pocket (with volume approximately x) centered at (pi,0). Further doping leads to the creation of a new holelike Fermi surface (volume approximately 1+x) centered at (pi,pi). These findings shed light on the Mott gap, its doping evolution, as well as the anomalous transport properties of the n-type cuprates.
authors.affiliation: Department of Physics, Applied Physics and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, California 94305, USA.
authors.forename: N P
authors.initials: NP
authors.lastname: Armitage
authors.forename: F
authors.initials: F
authors.lastname: Ronning
authors.forename: D H
authors.initials: DH
authors.lastname: Lu
authors.forename: C
authors.initials: C
authors.lastname: Kim
authors.forename: A
authors.initials: A
authors.lastname: Damascelli
authors.forename: K M
authors.initials: KM
authors.lastname: Shen
authors.forename: D L
authors.initials: DL
authors.lastname: Feng
authors.forename: H
authors.initials: H
authors.lastname: Eisaki
authors.forename: Z-X
authors.initials: ZX
authors.lastname: Shen
authors.forename: P K
authors.initials: PK
authors.lastname: Mang
authors.forename: N
authors.initials: N
authors.lastname: Kaneko
authors.forename: M
authors.initials: M
authors.lastname: Greven
authors.forename: Y
authors.initials: Y
authors.lastname: Onose
authors.forename: Y
authors.initials: Y
authors.lastname: Taguchi
authors.forename: Y
authors.initials: Y
authors.lastname: Tokura