Tunnelling spectra for (dx2-y2+ is)-wave superconductors versus tunnelling spectra for (dx2-y2+ idxy)-wave superconductors

Tunneling spectra for (dx2−y2 + is)-wave superconductors versus tunneling spectra for (dx2−y2 + idxy)-wave superconductors

The tunneling conductance spectra of a normal metal / insulator / singlet superconductor is calculated from the reflection amplitudes using the BlonderTinkham-Klapwijk (BTK) formulation. The pairing symmetry of the superconductor is assumed to be dx2−y2 + is, or dx2−y2 + idxy. It is found that in the (dx2−y2 + is)-wave case there is a well defined conductance peak in the conductance spectra, in...

Overscreening of magnetic impurities in dx2−y2 wave superconductors

We consider the screening of a magnetic impurity in a dx2−y2 wave superconductor. The properties of the dx2−y2 state lead to an unusual behavior in the impurity magnetic susceptibility, the impurity specific heat and in the quasiparticle phase shift which can be used to diagnose the nature of the condensed state. We construct an effective theory for this problem and show that it is equivalent t...

Novel neutron resonance mode in dx2-y2-wave superconductors.

We show that a new resonant magnetic excitation at incommensurate momenta, observed recently by inelastic neutron scattering experiments on YBa2Cu3O6.85 and YBa2Cu3O6.6, is a spin exciton. Its location in the Brillouin zone and its frequency are determined by the momentum dependence of the particle-hole continuum. We identify several features that distinguish this novel mode from the previous r...

Mixing of the order parameters with dx2-y2- and dxy-wave symmetry in d-wave superconductors.

Helical Majorana fermions in dx2−y2 + idxy-wave topological superconductivity of doped correlated quantum spin Hall insulators

There has been growing interest in searching for exotic self-conjugate, charge-neutral low-energy fermionic quasi-particles, known as Majorana fermions (MFs) in solid state systems. Their signatures have been proposed and potentially observed at edges of topological superconcuctors with non-trivial topological invariant in the bulk electronic band structure. Much effort have been focused on rea...