Zigzag filamentary theory of longitudinal optical phonons in high-temperature superconductors

摘要

Anomalous features (dispersive gaps and pseudogaps) have been observed by inelastic neutron scattering in the longitudinal optical bond-stretching vibrational spectra of superconductive (Ba0.6K0.4BiO3) and ferromagnetic (La1-xSrxMnO3) doped perovskites, as well as in layered superconductive pseudoperovskite cuprates La2-xSrxCuO4 (x = 0.15) and YBa2Cu3O6+x (x = 0.20, 0.35, 0.60 and 0.93). These anomalies are explained by a microscopic theoretical model which is compatible with the only known satisfactory fundamental model of superconductivity, namely the Bardeen-Cooper-Schrieffer theory. The model assumes that the dopants are self-organized into chains and planes with short-range orders of special symmetries. [References: 50]