COMPETITION BETWEEN CDW AND SUPERCONDUCTIVITY IN LOW-DIMENSIONAL ELECTRON-PROTON COUPLED SYSTEMS

From a new point of view, the competition between CDW and superconduct ivity is discussed in halogen-bridged mixed-valence transition-metal c omplexes. The light proton motion on the hydrogen bond between a ligan d and a counter anion is introduced in a strongly coupled form with th e one-dimensional electron system. It is concluded that protons modula te the electron-electron interaction, and the electron-proton coupling induces a strong attraction to lead superconductivity surpassing the CDW state.