Evidence for a charge collective mode associated with superconductivity in copper oxides from neutron and x-ray scattering measurements of La${}_{2-x}$Sr${}_x$CuO${}_4$

S. R. Park, T. Fukuda, A. Hamann +5

In superconducting copper oxides some Cu-O bond-stretching phonons around 70meV show anomalous giant softening and broadening of electronic origin and electronic dispersions have l…