Synchrotron study of oxygen depletion in a Bi-2212 whisker annealed at 363 K

J Synchrotron Radiat. 2009 Nov;16(Pt 6):813-7. doi: 10.1107/S0909049509036802. Epub 2009 Oct 1.

Abstract

Direct evidence is reported of structural and electronic effects induced on a single Bi(2)Sr(2)CaCu(2)O(8+delta) (Bi-2212) whisker during a progressive annealing process. The crystal was investigated by micro X-ray diffraction (micro-XRD), micro X-ray fluorescence and electrical characterization at the European Synchrotron Radiation Facility, during a series of three in situ thermal processes at 363 K. Each step increased the sample resistivity and decreased its critical temperature, up to a semiconducting behaviour. These data correlate with micro-XRD analysis, which shows an increase of the c-axis parameter from 30.56 A to 30.75 A, indicating an oxygen depletion mechanism. Mild temperature annealing could be an effective process to modulate the intrinsic Josephson junctions' characteristics in Bi-2212 whiskers.