Self-localized oscillations in high-temperature superconductors

Molecular-dynamic characterization of high-temperature superconductors is d iscussed. Results obtained show strong anharmonicity of self-localized high -frequency oscillations of individual atoms. The localization of these osci llations near certain defects results in the spatial redistribution of the kinetic energy in the system. By the example of the La-Sr-Cu-O system, it w as shown that the presence of the oscillations correlates with the supercon ductor transition temperature in this compound and causes fluctuations in t he phonon and soliton subsystems. This may be a reason for the occurrence o f high-temperature (high-T-c) superconductivity (HTSC). Calculations are co mpared with experimental data. (C) 2001 MAIK "Nauka/Interperiodica".