Growth related Y2BaCuO5 particle concentration micro-inhomogeneity in the growth sectors of TSMG YBa2Cu3O7/Y2BaCuO5 bulk superconductor

It is shown that a microscopic inhomogeneities in the Y2BaCuO5 (Y211) concentration in the growth sectors (GSs) of single-grain melt-grown YBa2Cu3O7 (12 3) bulks are associated with the development of growth subsectors (GSSs) which are formed due to the existence of macrosteps at the growth front. Formation of the c-GSS in the a-GS leads to local low Y211 concentration and on the other hand formation of the a-GSS in the c-GS causes a local increase in Y211 concentration. The anisotropy of the pushing-trapping phenomenon is responsible for observed changes in Y211 concentration. It is also shown that the macrosteps at the growth front can be created due to differences in the growth rate of subgrains. (C) 2002 Elsevier Science B.V. All rights reserved.