Accession Number : AD0712072

Title :   THE SECOND ENERGY GAP IN SUPERCONDUCTING NIOBIUM.

Descriptive Note : Technical rept.,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF METALLURGY AND MATERIALS SCIENCE

Personal Author(s) : Hafstrom,J. W. ; MacVicar,M. L. A.

Report Date : 24 SEP 1970

Pagination or Media Count : 29

Abstract : Low temperature tunneling studies of high purity single crystals of niobium indicate the existence of two energy gaps, delta sub s and delta sub d, one for each of the two bands lying at the Fermi level. The value of delta sub s i approximately delta sub d/19. The crystallographic dependence of delta sub s indicates that delta sub s does not appear in directions where there is no s-d overlap at E sub F. The behavior of delta sub s with temperature and magnetic field indicate that interband coupling is significant in niobium. The results are compared to current theories of multiband superconductivity.

Descriptors :   (*TUNNELING(ELECTRONICS), NIOBIUM), (*NIOBIUM, SUPERCONDUCTIVITY), SINGLE CRYSTALS, TRANSPORT PROPERTIES, BAND THEORY OF SOLIDS, OXIDES, INDIUM

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE