Lattice Effects on Charge Localization in Cuprates

Recent experimental results on cuprates and manganites, including those of elastic and inelastic neutron scattering measurements, suggest that charges are not homogeneously distributed even in the metallic state in these compounds. Charge inhomogeneity results from spin/lattice charge constriction. In cuprates the LO phonons strongly reflect the temperature- and composition-dependent charge inhomogeneity and may possibly be involved in causing it. Unlike the static stripes that compete against superconductivity, the charge inhomogeneity seen by the LO phonons is markedly increased in the superconducting phase. A new mechanism of high-temperature superconductivity involving lattice/spin charge constriction is proposed.