Preparation and characterization of ultrathin Bi2Sr2CaCu2O8 single crystals

Abstract

Optically transparent, free-standing single crystals of the high-temperature superconductor Bi2Sr2CaCu2O8 have been prepared with a typical size of a×b×c=1 mm×1 mm×1500 Å. The thickness of the samples has been determined by x-ray transmission measurements and was found to be uniform to within a lattice spacing. Transmission electron microscopy and diffraction revealed a pseudotetragonal lattice with a twinning free, incommensurate superstructure. X-ray microanalysis shows that the composition of the sample is homogeneous. Electrical resistivity and magnetic susceptibility measurements indicate that the crystals are good quality superconductors.