title: Influences of alkaline earth metal substitution on the crystal structure and physical properties of magnetic RuSr1.9A0.1GdCu2O8 (A = Ca, Sr, and Ba) superconductors.
abstract: We have investigated the effect of alkaline earth metal substitution on the crystal structure and physical properties of magnetic superconductors RuSr(1.9)A(0.1)GdCu(2)O(8) (A = Ca, Sr, and Ba) in order to probe an interaction between the magnetic coupling of the RuO(2) layer and the superconductivity of the CuO(2) layer. X-ray diffraction and X-ray absorption spectroscopic analyses demonstrate that the isovalent substitution of Sr ions with Ca or Ba ions makes it possible to tune the interlayer distance between the CuO(2) and the RuO(2) layers. From the measurements of electrical resistance and magnetic susceptibility, it was found that, in contrast to negligible change of magnetization, both of the alkaline earth metal substitutions lead to a notable depression of zero-resistance temperature T(c) (DeltaT(c) approximately 17-19 K). On the basis of the absence of a systematic correlation between the T(c) and the interlayer distance/magnetization, we have concluded that the internal magnetic field of the RuO(2) layer has insignificant influence on the superconducting property of the CuO(2) layer in the ruthenocuprate.
authors.affiliation: Center for Intelligent Nano-Bio Materials (CINBM), Division of Nano Sciences and Department of Chemistry, Ewha Womans University, Seoul 120-750, Korea.
authors.forename: Su Gil
authors.initials: SG
authors.lastname: Hur
authors.forename: Dae Hoon
authors.initials: DH
authors.lastname: Park
authors.forename: Seong-Ju
authors.initials: SJ
authors.lastname: Hwang
authors.forename: Seung Joo
authors.initials: SJ
authors.lastname: Kim
authors.forename: J H
authors.initials: JH
authors.lastname: Lee
authors.forename: Sang Young
authors.initials: SY
authors.lastname: Lee
mesh_terms: D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003300:Copper / Q000737:chemistry*; D003460:Crystallization; D004553:Electric Conductivity; D005682:Gadolinium / Q000737:chemistry*; D008280:Magnetics; D008673:Metals, Alkaline Earth / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D010316:Particle Size; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D008673:Metals, Alkaline Earth; D003300:Copper; D012428:Ruthenium; D005682:Gadolinium; D010100:Oxygen