Homogeneity assessment of YBa_2Cu_3O_(7-x) single crystals by cathodoluminescence microscopy

Abstract

Cathodoluminescence (CL) of YBa_2Cu_3O_(7-x) single crystals has been investigated in the scanning electron microscope, Some regions of the crystals, generally related to steps or other growth features, show enhanced CL Intensity. Spectra show the presence of two emission bands centered at about 2.85 and 2.3-2.4 eV, respectively. In the regions of higher CL intensity, the 2.3 eV band, which has been attributed to defects in the oxygen sublattice, shows a higher relative intensity. (C) 1996 Americans Institute of Physics.