SPIN AND CHARGE BIPOLARON KINETICS OF HIGH-T(C) SUPERCONDUCTORS

We extend the BSC theory to the strong electron-phonon (magnon) coupli ng limit. We show that the formation of small polarons and bipolarons provides a number of new physical phenomena both in the normal and sup erconducting states and explains low-energy physics of high-T(c) super conductors. Both lattice and spin (bi)polarons are discussed. A highly nonadiabatic motion of bipolarons leads to a unique physical nature o f (bi)polaronic superconductivity, making it totally different from th at of the BCS one, including its wellknown strong-coupling generalizat ion. The maximum attainable T(c) is estimated to be in the region of t he transition from the Fermi-liquid to a charged Bose-liquid. Some evi dence for 2e bosons is given from NMR, neutron scattering, near-infrar ed absorption, Hall effect, resistivity, thermal conductivity, and cri tical magnetic fields of high-T(c) oxides. An infinite thermal conduct ivity of two-dimensional charged bosons is predicted below T(c). The i nsulator-metal transition and ARPES in copper oxides are also discusse d. The proposed theory is not restricted by low dimensionality and mig ht be applied to cubic oxides like BaPbBiO and to alkali-doped C60.