Density of states of a layered S/Nd-wave superconductor

Abstract

We calculate the density of states of a layered superconductor in which there are two layers per unit cell. One of the layers contains a d-wave pairing interaction while the other is a normal metal. The goal of this article is to understand how the d-wave behaviour of the system is modified by the coupling between the layer-types. This coupling takes the form of coherent, single particle tunneling along the c-axis. We find that there are two physically different limits of behaviour, which depend on the relative locations of the Fermi surfaces of the two layer-types. We also discuss the interference between the interlayer coupling and pairing interaction and we find that this interference leads to features in the density of states.

Critical Josephson current in a model Pb/YBa2Cu3Atkinson1, Ćarbotte2 1995Phys. Rev. BSelf Cite111120View full textAdd to dashboardCite

“…This model is related to models studied elsewhere [29][30][31][32][33][34][35] in which both layers are treated as planes and (with the exception of Ref. [ 35] where it is d-wave ) the order parameter is s-wave. It should be emphasized that this model is only suitable for weak chain-plane coupling.…”

“…The strength of the plane-chain coupling is given by t(k) which, in the tight binding limit, depends 35 only on k z . To simplify matters further, we take the chain-plane distances to be the same on either side of a chain, so that…”

Quasiparticle tunneling spectra of the high-Tcmercury cuprates: Implications of thed-wave two-dimensional van Hove scenario

“…Some workers have considered spectral contributions from extrinsic causes such as chemical inhomogeneity, low barrier heights, 7 and single-electron charging of the junction, 8 in an effort to extract the quasiparticle DOS and to deduce ⌬. Others have focused on more intrinsic explanations such as interlayer coupling, 9,10 inelastic scattering by spin-fluctuations, and non-Fermi liquid phenomenology, [11][12][13][14][15][16] seeking to relate the tunneling anomalies to possible mechanisms responsible for high-T c superconductivity. Each of the models tends to be specialized to explain one or another of the tunneling anomalies without providing an unifying picture.…”

Triplanar model for the gap and penetration depth inYBa2Cu3O'Donovan1, Ćarbotte2 1997Phys. Rev. BSelf Cite12180View full textAdd to dashboardCite

“…These large anisotropies would not exist in a purely tetragonal system. The role of the chains in YBCO has been investigated before using a twoplane model 8 as well as a plane-chain model. 9,10 While these calculations have given us considerable insight, such a model is not fully realistic.…”