Universal scaling behavior of the c-axis resistivity of high-temperature superconductors

We propose and show that the c-axis transport in high-temperature superconductors is controlled by the pseudogap energy and the c-axis resistivity satisfies a universal scaling law in the pseudogap phase. We derived approximately a scaling function for the c-axis resistivity and found that it fits well with the experimental data of Bi2Sr2CaCu2O8+delta, Bi2Sr2Ca2Cu3O10+delta, and YBa2Cu3O7-delta. Our works reveals the physical origin of the semiconductorlike behavior of the c-axis resistivity and suggests that the c-axis hopping is predominantly coherent.