Interlayer quasiparticle transport in the vortex state of josephson coupled superconductors

We calculate the dependence of the interlayer quasiparticle conductivity, sigma(q), in a Josephson coupled d-wave superconductor on the magnetic field B parallelc and the temperature T. We consider a clean superconductor with resonant impurity scattering and a dominant coherent interlayer tunneling. When pancake vortices in adjacent layers are weakly correlated, at low T the conductivity increases sharply with B over a field scale determined by the impurity scattering, before reaching an extended region of slow linear growth. At high T the conductivity initially decreases and then reaches the same linear regime. For correlated pancakes, sigma(q) increases much more strongly with the applied field.