Dg. Ko et al., SUPERCONDUCTING AND MAGNETIC-PROPERTIES OF MATERIALS WITH VARYING CLUSTERING IN YBA2 (CU1-XMX)3O] WITH M = FE, CO, NI, Applied superconductivity, 1(7-9), 1993, pp. 1099-1102
Citations number
6
Categorie Soggetti
Material Science","Physics, Applied","Physics, Condensed Matter
We present structural, magnetic and superconducting properties of conv
entionally, and reductively prepared equilibrium states of YBa2(Cu1-xM
x)3Oy with M = Fe, Co, Ni. Depending on preparation conditions, varyin
g clustering tendencies for M on Cu(I) are found. A highly ordered clu
ster state (U) manifests itself in relatively high T(c) and strong ort
horhombicities amongst others. This has to do with the partial condens
ation of M into cluster domain walls. Mode and conditions for this clu
stering are different for different M. As an example, maximum values o
f T(c) at a given x are found at lower annealing temperatures for M =
Co compared to Fe both, experimentally and on a local thermodynamic mo
del. Comparisons of this model with data from Mossbauer spectroscopy a
re drawn. The clustered M = Fe materials show an increase in critical
currents through flux pinning on the Fe clusters, indicating technolog
ical potential.