title: Tunable metallicity of the La5/8Ca3/8MnO3(001) surface by an oxygen overlayer.
abstract: We studied the surface structure of La_{5/8}Ca_{3/8}MnO_{3}(001) thin films using in situ scanning tunneling microscopy (STM). Atomically resolved STM images reveal that a (sqrt[2]xsqrt[2])R45;{ degrees } reconstructed surface and a (1x1) surface can be converted back and forth through adsorption and desorption of oxygen at the surface. The electrical properties of the surfaces are investigated by scanning tunneling spectroscopy. I-V curves clearly show that the presence of an oxygen overlayer renders the surface insulating while the (1x1) surface without the oxygen overlayer is metallic.
authors.affiliation: Materials Sciences and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: K
authors.initials: K
authors.lastname: Fuchigami
authors.forename: Z
authors.initials: Z
authors.lastname: Gai
authors.forename: T Z
authors.initials: TZ
authors.lastname: Ward
authors.forename: L F
authors.initials: LF
authors.lastname: Yin
authors.forename: P C
authors.initials: PC
authors.lastname: Snijders
authors.forename: E W
authors.initials: EW
authors.lastname: Plummer
authors.forename: J
authors.initials: J
authors.lastname: Shen