title: Correlated electron state in Ce(1-x)Yb(x)CoIn5 stabilized by cooperative valence fluctuations.
abstract: X-ray diffraction, electrical resistivity, magnetic susceptibility, and specific heat measurements on Ce(1-x)Yb(x)CoIn5 (0≤x≤1) reveal that many of the characteristic features of the x=0 correlated electron state are stable for x≤0.775 and that phase separation occurs for x>0.775. The stability of the correlated electron state is apparently due to cooperative behavior of the Ce and Yb ions, involving their unstable valences. Low-temperature non-Fermi liquid behavior is observed and varies with x, even though there is no readily identifiable quantum critical point. The superconducting critical temperature T(c) decreases linearly with x towards 0 K as x→1, in contrast with other HF superconductors where T(c) scales with T(coh).
authors.affiliation: Department of Physics, University of California, San Diego, La Jolla, California 92093, USA.
authors.forename: L
authors.initials: L
authors.lastname: Shu
authors.forename: R E
authors.initials: RE
authors.lastname: Baumbach
authors.forename: M
authors.initials: M
authors.lastname: Janoschek
authors.forename: E
authors.initials: E
authors.lastname: Gonzales
authors.forename: K
authors.initials: K
authors.lastname: Huang
authors.forename: T A
authors.initials: TA
authors.lastname: Sayles
authors.forename: J
authors.initials: J
authors.lastname: Paglione
authors.forename: J
authors.initials: J
authors.lastname: O'Brien
authors.forename: J J
authors.initials: JJ
authors.lastname: Hamlin
authors.forename: D A
authors.initials: DA
authors.lastname: Zocco
authors.forename: P-C
authors.initials: PC
authors.lastname: Ho
authors.forename: C A
authors.initials: CA
authors.lastname: McElroy
authors.forename: M B
authors.initials: MB
authors.lastname: Maple