Improved Bi-(2 2 0 1) single crystals grown in cavities formed in KCl solution-melt

Abstract Perfect superconducting Bi-(2 2 0 1) single crystals were obtained in cavities formed into the KCl solution-melt. The X-ray diffraction profiles of these crystals show no detectable subcell defects. At the same time, it can be deduced from satellite reflection studies that there are two types of supercell variations: either changes along the a axis in conjunction with a small supercell rotation about the b axis or changes along the c axis. In our opinion, these supercell variations are directly related to light composition oscillations during a layer crystal growth.