Unusual features in the normal-state resistivity of Bi2Sr2Ca2Cu2O10 whiskers

Features in the normal-state resistivity of underdoped Bi2Sr2Ca2Cu3O10 (Bi-2223) single crystals have been observed,in which an upturn deviation from the linear rho - T, rather than the usual downturn drop, appeared below T*-250 K. While rho keeps decreasing with T, the "excess resistivity," Delta rho drop rho-(a + bT), seems to follow an empirical power law: proportional to(1 - T/T*)(n), n= 1.5-2, within a transition region (T' <T<T*). For T <T'similar to 200 K, Delta rho is either inversely dependent on T or saturated (N-2 annealed samples). Such behavior may result from structural transformations and charge dynamics similar to those in the stripe phases. [S0163-1829(99)03629-2].