Spiral growth, flux pinning and peak effect in doped and pure Bi-2212 high temperature superconducting single crystals

This thesis consists of two parts. The first part focuses on studies of the spiral growth pure Bi-2212 single crystals. The second part reports on magnetization peak effects in pure and doped Bi-2212 crystals grown through two-dimensional layer-by-layer or spiral growth mechanisms. Part I. An overview of the research on high temperature superconducting (HTS) single crystals in the period from the end of 1994 to the beginning of 1999 is provided. There is a particular focus on single crystal growth of Y-Ba-Cu-O, Bi-Sr-Ca-Cu-O, and Tl-Ba-Ca-cu-O and their characterisation for different compounds. The related questions of the electric and magnetic properties of HTS single crystals are also reviewed. Part II. Published work on an anomalous magnetization peak effect (PE) in HTS is reviewed Crystals defects, impurity inclusions, and oxygen defects have been regarded as directly responsible for the peak effect. From the viewpoint of flux pinning, edge barriers, dimensional crossover, softening of C44, and the order - disorder transition have also been proposed to explain the origin of the peak effect. In this thesis there is a particular focus the peak effect in Y-123 and Bi-2212 crystals.