COMPOSITION, STRUCTURE, AND ELECTRICAL-PROPERTIES OF BI2SR2CA1-YYYCU2O8 - A SINGLE-CRYSTAL STUDY

A systematic study of yttrium substitution for calcium in the high-temperature superconductor Bi2Sr2CaCu2O8 has been performed. Single crystals were grown, cleaved, and characterized with use of x-ray fluorescence, electron microprobe, and electron- and x-ray-diffraction techniques. The dc resistivity, diamagnetic shielding, and Hall coefficient of the samples were also measured as functions of the temperature from 4 to 300 K for different dopant concentrations. We conclude that our systematic substitution in the family Bi2Sr2Ca1-yYyCu2O8 gives an insight into this high-temperature superconducting material as well as into weak localization and metal-insulator transitions.