Interlayer coupling and c-axis quasiparticle transport in high-T-c cuprates - art. no. 054526

The c-axis quasiparticle conductivity shows different behavior depending on the nature of the interlayer coupling. For coherent coupling with a consta nt hopping amplitude t(perpendicular to), the conductivity at zero frequenc y and zero temperature sigma (0,0) depends on the direction of the magnetic field, but it does not for angle-dependent hopping t(phi) which removes th e contribution of the nodal quasiparticles. For incoherent coupling, the co nductivity is also independent of field direction and changes only when par amagnetic effects are included. The conductivity sum rule can be used to de termine the admixture of coherent to incoherent coupling. The value of sigm a (0,0) can be dominated by t(perpendicular to) while at the same time t(ph i) dominates the temperature dependence of the superfluid density.