Incipient Modulation in the New High-Temperature Superconductor: Tl2Ba2 CaCu2O8

Abstract

Electron diffraction patterns of the Tl-based superconductor ${\mathrm{Tl}}_2$ ${\mathrm{Ba}}_2$ Ca${\mathrm{Cu}}_2$ ${\mathrm{O}}_8$ display characteristic rings of diffuse intensity about space-group-forbidden reflections. There exists a close relationship between this diffuse intensity distribution and the incommensurate modulation observed in the structurally related Bi-based superconductor ${\mathrm{Bi}}_2$ ${\mathrm{Sr}}_2$ Ca${\mathrm{Cu}}_2$ ${\mathrm{O}}_8$.