Unconventional Mott transition in KxFe2-ySe2

Article

关键词: ELECTRONIC-STRUCTURE CALCULATIONS;    MEAN-FIELD THEORY;    INSULATOR;    SUPERCONDUCTIVITY;    FESE;   

DOI  :  10.1103/PhysRevB.84.224520

来源: SCIE

【 摘 要 】

The newly discovered 122-iron-chalcogenide superconductors show clear signatures of Mott-insulating and strange, incoherent metal normal states. Motivated thereby, we use local-density approximation plus dynamical mean-field theory (LDA + DMFT) to study the electronic structure and transport properties of KxFe2-ySe2. We find that the undoped KFe1.6Se2 system is a new kind of Mott-Kondo insulator (MKI). Electron doping this MKI drives a Mott transition to an orbital-selective non-Fermi-liquid metal. Good agreement with spectral and transport responses supports our view, implying that superconductivity arises from a doped Mott insulator, as in the high-T-c cuprates.

【 授权许可】

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