Understanding superconductivity in K₂Cr₃As₃

The discovery of superconductivity in quasi-one-dimensional K₂Cr₃As₃ has opened new avenues to study the arrival of superconductivity from strongly correlated electronic behavior. With a non-centrosymetric structural motif of CrAs double walled tubes built of layered truncated Sierpinski triangles with interior Cr atoms and exterior As atoms, this material is a playground of possible exotic states ranging from Luttinger Liquids to Fulde-Feerel-Larkin-Ovchinnikov vortex lattices. Furthermore, early density functional theory calculations have predicted myriad magnetic ground states, including a ferromagnetic instability which together with the results of transport and local probe measurements have been taken to suggest a possible spin-triplet superconducting state. Yet despite these exciting possibilities, few reports have measured directly any exotic state and the nature of the superconducting state and the relevant fluctuations out of which it arises remains unknown. In this presentation we report on neutron scattering work which helps elucidate the relevant orders in this system.