title: Severe Fermi surface reconstruction at a metamagnetic transition in Ca2-xSrxRuO4 (for 0.2 <or=x<or=0.5).
abstract: We report an electrical transport study in Ca2-xSrxRuO4 single crystals at high magnetic fields (B). For x=0.2, the Hall constant Rxy decreases sharply at an anisotropic metamagnetic transition, reaching its value for Sr2RuO4 at high fields. A sharp decrease in the coefficient of the resistivity T2 term and a change in the structure of the angular magnetoresistance oscillations for B rotating in the planes confirms the reconstruction of the Fermi surface. Our observations and local-density-approximation calculations indicate a strong dependence of the Fermi surface on Ca concentration and suggest the coexistence of itinerant and localized electronic states in single layered ruthenates.
authors.affiliation: National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306, USA.
authors.forename: L
authors.initials: L
authors.lastname: Balicas
authors.forename: S
authors.initials: S
authors.lastname: Nakatsuji
authors.forename: D
authors.initials: D
authors.lastname: Hall
authors.forename: T
authors.initials: T
authors.lastname: Ohnishi
authors.forename: Z
authors.initials: Z
authors.lastname: Fisk
authors.forename: Y
authors.initials: Y
authors.lastname: Maeno
authors.forename: D J
authors.initials: DJ
authors.lastname: Singh