Unconventional superconductivity from electronic dipole fluctuations

The authors show that electric dipole fluctuations of Fermi-surface states are a possible source of unconventional superconductivity, especially in the presence of parity-mixing and spin-orbit coupling as is the case for Dirac metals. For the latter, they find a leading state analogous to the ${}^{3}$He-$B$ phase and a competitive subleading $p$-wave state. They also show that the proposed pairing glue is directly measurable in the optical conductivity.