Superconducting critical temperature T/sub c/ and electronic structure of pseudoternary Y(Rh/sub 1-x/Ru/sub x/)/sub 4/B/sub 4/ studied by high-resolution photoelectron spectroscopy

Journal Article · Sun Sep 01 00:00:00 EDT 1985 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.32.2895· OSTI ID:5386075

Knauf, R; Adrian, H; Meinelt, A; Johnson, R L

High-resolution photoemission measurements using synchrotron radiation are presented for the body-centered-tetragonal superconducting pseudoternary system Y(Rh/sub 1-x/Ru/sub x/)/sub 4/B/sub 4/ covering the range of composition 0.10< or =x< or =0.90. The superconducting phase diagram determined down to 4 mK reproduces the sharp drop in the superconducting critical temperature T/sub c/ for x>x/sub cr/ = 0.35, which is characteristic for this class of compound. No superconductivity was observed for the sample with x = 0.70, whereas the sample with x = 0.90 became superconducting again at T/sub c/ = 140 mK. From a comparison between the valence-band spectra near the Fermi level E/sub F/ and band-structure calculations by Jarlborg et al. for the related compounds MRh/sub 4/B/sub 4/ with M = Y, Gd, Ho, Er, and Lu, we conclude that a shift of E/sub F/ to lower energies with increasing x is the underlying mechanism for the T/sub c/(x) behavior. In our previous study on Ho(Rh/sub 1-x/Ru/sub x/)/sub 4/B/sub 4/, for which supplementary data are also presented, the same features were observed. Our measurements indicate that hybridization effects upon alloying Ru for Rh cannot explain the observed behavior of T/sub c/.

• Research Organization: Physikalisches Institut der Universitaet ErlangenNuernberg, Erwin-Rommel-Strasse 1, D-8520 Erlangen, Federal Republic of Germany
• OSTI ID: 5386075
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 32:5
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
RHODIUM BORIDES
ELECTRONIC STRUCTURE
PHOTOELECTRON SPECTROSCOPY
SUPERCONDUCTIVITY
TRANSITION TEMPERATURE
RUTHENIUM BORIDES
YTTRIUM BORIDES
EXPERIMENTAL DATA
HYBRIDIZATION
PHASE DIAGRAMS
STOICHIOMETRY
SYNCHROTRON RADIATION
TETRAGONAL LATTICES
ULTRAHIGH VACUUM
ULTRALOW TEMPERATURE
BORIDES
BORON COMPOUNDS
BREMSSTRAHLUNG
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DATA
DIAGRAMS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTROMAGNETIC RADIATION
ELECTRON SPECTROSCOPY
INFORMATION
NUMERICAL DATA
PHYSICAL PROPERTIES
RADIATIONS
REFRACTORY METAL COMPOUNDS
RHODIUM COMPOUNDS
RUTHENIUM COMPOUNDS
SPECTROSCOPY
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
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