This paper presents a microscopic calculation of the flux-flow resistivity $\rho_{ f}$ for s-wave type-II superconductors with arbitrary impurity concentrations near the upper critical field $H_{ c2}$. It is found that, as the mean free path $l$ becomes longer, $\rho_{ f}$ increases gradually from the dirty-limit result of Thompson [Phys. Rev. B{ \bf 1}, 327 (1970)] and Takayama and Ebisawa [Prog. Theor. Phys. { \bf 44}, 1450 (1970)]. The limiting behaviors suggest that $\rho_{ f}(H)$ at low temperatures may change from convex downward to upward as $l$ increases, thus deviating substantially from the linear dependence $\rho_{ f}\propto H/H_{ c2}$ predicted by the Bardeen-Stephen theory [Phys. Rev. { \bf 140}, A1197 (1965)].
Categories: cond-mat.supr-con