Recent theories of superconductivity based on the exchange of AFM spin-fluctuations argue for an unconventional spin-singlet order parameter with dx2-y2 symmetry. One important feature of this state is that the excitation gap has nodal lines on the Fermi surface. We show that the low-energy quasiparticle states near the nodes give rise to characteristic anomalies in the surface impedance which can be used to locate the positions of the nodes of an unconventional gap in momentum space.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering