Low-temperature metal-insulator transition in the electron-doped iron chalcogenide FeSe superconductor
Max-Planck-Institut für Chemische Physik fester Stoffe - 01187 Dresden, Germany, EU
2 Technische Universität Dortmund, Lehrstuhl für Theoretische Physik I - 44221 Dortmund, Germany, EU
Accepted: 7 July 2010
The normal state of the iron chalcogenide superconductors shows a range of inexplicable features. Both bad metallic resistivity, characteristic pseudogap features and proximity to insulating states mark these systems as correlated non-Fermi liquid metals. Here, using the LDA+DMFT scheme with sizable multi-orbital correlations, we show how the incoherent non-Fermi liquid metallic state of tetragonal-FeSe superconductor is inherently unstable to the specific kind of insulator seen in experiments. We describe the metal-insulator transition in electron-doped FeSe microscopically, along with implications for the low-temperature specific heat and static spin susceptibility.
PACS: 74.70.-b – Superconducting materials other than cuprates / 71.30.+h – Metal-insulator transitions and other electronic transitions / 71.27.+a – Strongly correlated electron systems; heavy fermions
© EPLA, 2010