Photoelectron microscopy and spectroscopy of Bi2Sr2-x- Ca1+xCu2O8+y(100)

The combination of photoelectron microscopy (PEM) and photoelectron spectroscopy (PES) from very small spatial regions enabled an in situ examination of the structural and electronic properties of sheets of cleaved single crystals of Bi2Sr2-xCa1+xCu2O8+y(100). The PEM images were obtained with 10 m spatial resolution, and the PES spectra were acquired from areas of 20 m diameter. The PEM images revealed the laminated structure of the surface in which thin sheets of single crystals with a typical dimension of 1×1 mm2 have highly stepped borders. PES spectra obtained as a function of distance across these complex structures demonstrated inhomogeneous bonding configurations with Bi atoms that are highly oxidized at the edge of each crystal.