COHERENT AB-TRANSPORT AND C-TRANSPORT-THEORY OF HIGH-T-C CUPRATES

We propose a microscopic theory of the normal state transport in coppe r oxides based on the bipolaron theory which describes qualitatively t he temperature (T) and doping (x) dependence of the in-plane rho(ab) a nd out-of-plane rho(c) resistivity and the spin susceptibility chi(s) in underdoped, optimally doped, and not very heavily overdoped La2-xSr xCuO4 for the temperature range from T-c up to 600 K. A free parameter relation between the anisotropy and the spin susceptibility is derive d, rho(c)(T,x)/rho(ab)(T,x) similar to x/T(1/2)chi(s)(T,x), which agre es quantitatively with the experiment. The normal state gap is explain ed and its doping and temperature dependence clarified.