Domain configurations of the "incommensurate" structures of 2H-TaSe2 and Bi2Sr2(Ca1-xLn(x))Cu2O8+delta studied by HRTEM

ABSTRACT

High-resolution transmission electron microscopy (HRTEM) images of the "incommensurate" structures of 2H-TaSe2 and Bi2Sr2Ca1-xLnx Cu2O8+delta (Ln rare earth metal) are shown. They were taken from a wide specimen area with homogeneous thickness. For the former, a configuration of two domains was found by a scrutiny of HRTEM images. For the latter, many configurations of two domains were extracted from the photometric density distribution in the one-dimensional contrast modulations in HRTEM images. One domain of the two in both configurations is created by a phase slip occurring in the primary atomic displacement longitudinal wave.