Theory of two-fluid metallicity in superconducting FeSe at high pressure

We compute the two-fluid resistivity of a compressed FeSe superconductor, treating electronic correlations within density functional dynamical mean-field theory. Results for the emergent strange and bad metal behavior shows good theory-experiment agreement within the mixed tetragonal and pseudohexagonal structural phases at pressures around 8.1 GPa. Our findings call for more studies on unconventional high-temperature (high-T-c) superconductors to unearth the consequences of selective Mott localization as the prominent candidate in governing their strange, T-linear resistivity.