Physics – Condensed Matter – Superconductivity
Scientific paper
2007-02-11
Phys. Rev. B 75, 214512 (2007)
Physics
Condensed Matter
Superconductivity
17 pages, 21 figures
Scientific paper
10.1103/PhysRevB.75.214512
We study the electronic structure in the vicinity of a vortex in a two-band superconductor in which the quasiparticle motion is ballistic in one band and diffusive in the other. This study is based on a model appropriate for such a case, that we have introduced recently [Phys. Rev. B 73, 220501(R) (2006)]. We argue that in the two-band superconductor MgB_2 such a case is realised. Motivated by the experimental findings on MgB_2, we assume that superconductivity in the diffusive band is ``weak'', i.e., mostly induced. We examine intriguing features of the order parameter, the current density, and the vortex core spectrum in the ``strong'' ballistic band under the influence of hybridization with the ``weak'' diffusive band. Although the order parameter in the diffusive band is induced, the characteristic length scales in the two bands differ due to Coulomb interactions. The current density in the vortex core is dominated by the contribution from the ballistic band, while outside the core the contribution from the diffusive band can be substantial, or even dominating. The current density in the diffusive band has strong temperature dependence, exhibiting the Kramer-Pesch effect when hybridization is strong. A particularly interesting feature of our model is the possibility of additional bound states near the gap edge in the ballistic band, that are prominent in the vortex centre spectra. This contrasts with the single band case, where there is no gap-edge bound state in the vortex centre. We find the above-mentioned unique features for parameter values relevant for MgB_2.
Agterberg Daniel F.
Eschrig Matthias
Tanaka Kanenobu
No associations
LandOfFree
Theory of vortices in hybridized ballistic/diffusive-band superconductors does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Theory of vortices in hybridized ballistic/diffusive-band superconductors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Theory of vortices in hybridized ballistic/diffusive-band superconductors will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-538498