M. Hayashi, L. Thomas, et al.
EPL
Bulk superconductivity is reported in Tl2Ca2Ba2 Cu3Ox with a transition to zero resistance at 125 K, the highest transition temperature (Tc) yet found. Transmission electron spectroscopy shows that the unit cell is body-centered tetragonal and contains trilayer Cu perovskitelike units separated by bilayer Tl-O units. Tc in this material varies from 118 to 125 K depending on preparation conditions. A high density of perovskitelike bilayer intergrowths are observed in the 118-K material, which we speculate result in the decreased Tc. A second structure containing only bilayer perovskitelike units Tl2Ca1Ba2Cu2Ox is a bulk superconductor with Tc ranging from 95 to 108 K. © 1988 The American Physical Society.
M. Hayashi, L. Thomas, et al.
EPL
S.S.P. Parkin, E.M. Engler, et al.
Physical Review B
R.E. Dunin-Borkowski, M.R. McCartney, et al.
Ultramicroscopy
W.J. Gallagher, D.W. Abraham, et al.
VLSI Technology 2005