Interlayer c-axis transport in the normal state of cuprates
  A theoretical model of c-axis transport properties in cuprates is proposed. Inter-plane and in-plane charge fluctuations make hopping between planes incoherent and diffusive (the in-plane momentum is not conserved after tunneling). The non-Drude optical conductivity $\sigma_c(\omega)$ and the power-law temperature dependence of the {\it dc} conductivity are generically explained by the strong fluctuations excited in the process of tunneling. Several microscopic models of the charge fluctuation spectrum are considered. 
Misha Turlakov and Anthony J. Leggett