Neutron diffraction study of the lattice distortion related to charge ordering inSr14Cu24O41

Abstract

Using elastic neutron scattering on a triple axis spectrometer we have studied the temperature dependence of the crystal structure in ${\mathrm{Sr}}_{14}{\mathrm{Cu}}_{24}{\mathrm{O}}_{41}$ across the range where charge ordering phenomena are expected. Several superstructure reflections are observed at low temperature which fully disappear above $\ensuremath{\sim}200\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. Most of these reflections can be explained by a modulation of both the chain and the ladder-lattices due to the charge ordering. However, the peak position as well as some weaker reflections point to a close connection between the charge ordering and the modulations of the incommensurate composite structure.