title: Quenching of majority-channel quasiparticle excitations in cobalt.
abstract: The low-energy electronic excitations in cobalt are studied by a theoretical method that includes many-body effects and a realistic description of the band structure. Angle-resolved photoemission spectra measured on a thick film of hexagonal close-packed Co on Cu(111) agree well with calculated spectral functions. Because of many-body effects no sharp quasiparticle peaks exist for binding energies larger than 2 eV and in this energy region the spectrum is essentially incoherent. The many-body corrections are much stronger in the majority-spin channel and drastically affect the spin polarization of the spectra.
authors.affiliation: INFM-S3 and Dipartimento di Fisica, Università di Modena, Via Campi 213/a, I-41100 Modena, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Monastra
authors.forename: F
authors.initials: F
authors.lastname: Manghi
authors.forename: C A
authors.initials: CA
authors.lastname: Rozzi
authors.forename: C
authors.initials: C
authors.lastname: Arcangeli
authors.forename: E
authors.initials: E
authors.lastname: Wetli
authors.forename: H-J
authors.initials: HJ
authors.lastname: Neff
authors.forename: T
authors.initials: T
authors.lastname: Greber
authors.forename: J
authors.initials: J
authors.lastname: Osterwalder