Superconductivity and crystal and electronic structures in hydrogenated and disordered Nb/sub 3/Ge and Nb/sub 3/Sn layers with A15 structure

Journal Article · Thu Aug 01 04:00:00 EDT 1985 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.32.1519· OSTI ID:5428590

Noelscher, C; Saemann-Ischenko, G

Superconducting and transport properties of Nb/sub 3/Ge and Nb/sub 3/Sn layers have been varied over a wide range by hydrogenation, ion irradiation, and annealing. After hydrogenation, both compounds remain in the A15 structure and no effects of hydride precipitations at low temperatures could be observed. At high ion-irradiation doses Nb/sub 3/Ge becomes amorphous, but Nb/sub 3/Sn remains in the A15 structure, although T/sub c/ behaves similarly. The long-range order parameter S/sub A/ and the mean displacement amplitude /sup 1/2/ were determined for Nb/sub 3/Sn with x-ray diffraction. Distinct differences between the irradiation- and annealing-induced correlations of T/sub c/ versus S/sub a/, T/sub c/ versus , and T/sub c/ versus lattice parameter were observed. This indicates the influence of topological short-range order. The correlations of T/sub c/ versus residual resistivity and T/sub c/ versus the temperature derivative of the upper critical field at T/sub c/ are distinctly different for hydrogenated and irradiated Nb/sub 3/Sn and Nb/sub 3/Ge, but the derived correlations of T/sub c/ versus the coefficient of the electronic specific heat are very similar. The results are interpreted by a dominant influence of the GAMMA/sub 12/ band on high T/sub c/. The measurements of the Hall constant R/sub H/ indicate a filling of steep electronic bands as a result of hydrogenation. Irradiation has a similar influence as thermal-induced disorder on R/sub H/.

• Research Organization: Physikalisches Institut der Universitat Erlangen-Nuernberg, Erwin-Rommel-Strasse 1, 8520 Erlangen, Federal Republic of Germany
• OSTI ID: 5428590
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 32:3; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
AMORPHOUS STATE
ANNEALING
BETA-W LATTICES
CHEMICAL REACTIONS
COLLISIONS
CRITICAL FIELD
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DATA
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRONIC STRUCTURE
EXPERIMENTAL DATA
GERMANIUM COMPOUNDS
HALL EFFECT
HEAT TREATMENTS
HYDROGENATION
INFORMATION
ION COLLISIONS
LAYERS
MAGNETIC FIELDS
NIOBIUM COMPOUNDS
NUMERICAL DATA
PHYSICAL PROPERTIES
RADIATION EFFECTS
REFRACTORY METAL COMPOUNDS
SUPERCONDUCTIVITY
THERMODYNAMIC PROPERTIES
TIN COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE