title: High-resolution photoemission spectroscopy for the layered antiferromagnetic (La(1-z)Nd(z))(0.46)Sr(0.54)MnO(3).
abstract: High-resolution HeI photoemission spectroscopy (UPS), Mn 2p-3d resonant photoemission spectroscopy (RPES) and Mn 2p X-ray absorption spectroscopy (XAS) have been performed to investigate the electronic structure and its effect on the electrical resistivity in (La(1-z)Nd(z))(0.46)Sr(0.54)MnO(3) (z = 0, 0, 2, 0.6 and 1.0). It was found that in the UPS and RPES spectra the Fermi edge persisted over the temperature range 15 < or = T < or = 340 K regardless of the magnetic structure or the composition of the samples. The density of states at the Fermi level [N(E(F))] in the samples where 0 < or = z < or = 0.6 was increased drastically at the Curie temperature (T(C)) with decreasing temperature, but essentially kept unchanged across the Néel temperature (T(N)). A fairly large reduction at T(C) and a small increase at T(N) in the electrical resistivity with decreasing temperature are found to be well accounted for in terms of the temperature dependence of N(E(F)). The presence of a finite N(E(F)) in the insulating Nd(0.46)Sr(0.54)MnO(3) was also found. Thus the origin of the insulating behavior in this sample can be regarded as the Anderson localization associated with the small density of states and the chemical disorder between Nd and Sr.
authors.affiliation: Department of Crystalline Materials Science, Nagoya University, Nagoya 464-8603, Japan. takeuchi@nuap.nagoya-u.ac.jp
authors.forename: Tsunehiro
authors.initials: T
authors.lastname: Takeuchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nozaki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Soda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kondo
authors.forename: Mizutani
authors.initials: M
authors.lastname: Uichiro
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Yokoya
authors.forename: Takafumi
authors.initials: T
authors.lastname: Sato
authors.forename: Takashi
authors.initials: T
authors.lastname: Takahashi
authors.forename: Shik
authors.initials: S
authors.lastname: Shin
authors.forename: Takayuki
authors.initials: T
authors.lastname: Muro
authors.forename: Yuji
authors.initials: Y
authors.lastname: Saitoh
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Moritomo