Collective d-wave exciton modes in the calculated Raman spectrum of Fe-based superconductors

Calculations of the pairing interaction in multiband models of the Fe superconductors show that it is attractive in both the A(1g) (s-wave) and B(1g) (d-wave) channels. This raises the possibility that these materials may have collective excitonic modes. Here, assuming an s-wave ground state, we investigate the d-wave collective excitonic mode and its coupling to the Raman scattering.