C-axis optical conductivity in cuprates

Abstract

We investigate the c-axis optical conductivity and DC resistivity of cuprate superconductors in the normal state. Assuming that the interlayer hopping is incoherent we express the conductivity with planar spectral functions obtained (i) from angle-resolved photoemission experiments (ARPES), (ii) using marginal Fermi liquid (MFL) ansatz, and (iii) with the finite-temperature Lanczos method for finite two-dimensional systems described by the t– J model. In the optimally doped regime anomalous relaxation rate τ c −1∝ ω+ ξ c T found by Prelovšek et al. (Phys. Rev. Lett. 81 (1998) 3745) is analytically reproduced with the use of the marginal Fermi liquid ansatz for the self energy with parameters obtained from the exact diagonalization results. A semimetallic-like behavior of ρ c( T) in the low doping regime emerges due to a pseudo-gap opening in the density of states.