Effects of chromium and manganese on the superconducting density of states of niobium and vanadium

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5380336

Buchanan, D S

Proximity effect electron tunneling measurements were made on Nb-Cr, Nb-Mn, V-Cr, and V-Mn films. These films were prepared in an MBE system and in the case of the V films they were grown epitaxialy on sapphire substrates. When the data for Nb are compared to Shiba's theory for magnetic dopants in superconductors, the no states are seen which are localized in energy as Shiba predicts although there is some indication that there are some states in the gap which are smeared out. For V there are no indications of any states in the gap suggesting that low concentrations of Mn and Cr are not magnetic in V. The smearing of the gap edge present in the I-V characteristics of a pure Nb sample was also looked at. It was seen that the degree of smearing of the gap edge is consistent with surface impedance measurements on Nb, and that it can be related to the fact that the density of state at the Fermi energy in Nb lies on the side of a very sharp peak in the density of states.

• Research Organization: Illinois Univ., Urbana (USA)
• OSTI ID: 5380336
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
656102 -- Solid State Physics-- Superconductivity-- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena-- (-1987)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CHROMIUM
DATA
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
ENERGY GAP
ENERGY-LEVEL DENSITY
EXPERIMENTAL DATA
FILMS
INFORMATION
MANGANESE
MATERIALS
METALS
NIOBIUM
NUMERICAL DATA
PHYSICAL PROPERTIES
PROXIMITY EFFECT
SUPERCONDUCTIVITY
TRANSITION ELEMENTS
TUNNEL EFFECT
VANADIUM