title: Origin of metallic states at the heterointerface between the band insulators LaAlO3 and SrTiO3.
abstract: We have studied the electronic structure at the heterointerface between the band insulators LaAlO3 and SrTiO3 using in situ photoemission spectroscopy. Our experimental results clearly reveal the formation of a notched structure on the SrTiO3 side due to band bending at the metallic LaAlO3/TiO2-SrTiO3 interface. The structure, however, is absent at the insulating LaAlO3/SrO-SrTiO3 interface. The present results indicate that the metallic states originate not from the charge transfer through the interface on a short-range scale but from the accumulation of carriers on a long-range scale.
authors.affiliation: Department of Applied Chemistry, University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yoshimatsu
authors.forename: R
authors.initials: R
authors.lastname: Yasuhara
authors.forename: H
authors.initials: H
authors.lastname: Kumigashira
authors.forename: M
authors.initials: M
authors.lastname: Oshima