Title :
Multi-phase structure of thermally diffused niobium nitride
Author :
Fabbricatore, P. ; Musenich, R. ; Occhetto, M. ; Parodi, R. ; Pompa, P. ; Merlo, F.
Author_Institution :
Istituto Nazionale di Fisica Nucl., Genova, Italy
fDate :
3/1/1991 12:00:00 AM
Abstract :
In order to study superconducting niobium nitrides for RF applications, Nb-N samples obtained by diffusion of nitrogen in bulk niobium were investigated. X-ray diffraction and AC susceptibility measurements were performed. From these measurements, the composition and the critical parameters (Hc1 and Jc) of the material were deduced. The results for several samples are compared. It is shown that the proposed method allows detection of the presence of different superconducting phases and granularity of materials. It was used to understand the RF behaviour of Nb-N (high residual surface resistance). Although the measured samples did not show granularity, the presence of several materials with different superconducting properties was observed. Low-Tc phases were always detected in the samples, sometimes also at the surface
Keywords :
X-ray diffraction examination of materials; critical current density (superconductivity); niobium compounds; superconducting critical field; surface conductivity; type II superconductors; AC susceptibility; Hc1; Jc; NbNx; RF applications; X-ray diffraction; composition; critical parameters; diffusion; granularity; high residual surface resistance; superconducting; Composite materials; Electrical resistance measurement; Niobium compounds; Nitrogen; Performance evaluation; Phase detection; Radio frequency; Superconducting materials; Surface resistance; X-ray diffraction;
Journal_Title :
Magnetics, IEEE Transactions on
