High-frequency electrodynamic response of strongly anisotropic clean normal and superconducting metals

We consider the influence of quasiparticle relaxation and nonlocality on the complex conductivity and microwave surface impedance of isotropic and quasi-two-dimensional metals in the normal and superconducting states for arbitrary electronic parameters intermediate between the classical skin effect and extreme anomalous limits. We describe the superconducting state by a two-fluid model with a nonlocal, retarded quasiparticle response and derive an expression for the surface impedance at low temperatures in the extreme anomalous limit. We show how microwave measurements can be used to probe the k dependence of the superconducting order parameter in layered materials.