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Selective orbital reconstruction in tetragonal FeS: A density functional dynamical mean-field theory study
1Instituto de Física, Universidade Federal de Mato Grosso, Cuiabá, MT, 78060-900, Brazil.
Scientific Reports
|April 19, 2017
Summary
Tetragonal iron monosulfide exhibits complex semiconducting and metallic behaviors due to its d-band system. Density functional dynamical mean-field theory explains these properties and suggests tuning electron-doped FeS could lead to unconventional superconductivity.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Tetragonal iron monosulfide (mackinawite) displays complex transport properties.
- Its d-band system exhibits semiconductive behavior and proximity to metallic states with superconductivity, classifying it as an unconventional quantum material.
Purpose of the Study:
- To comprehensively explain the dual semiconducting and metallic responses in tetragonal FeS.
- To contrast these properties with tetragonal FeSe, a pseudogapped metal above its superconducting transition temperature.
- To characterize the paramagnetic insulating and metallic phases of mackinawite.
Main Methods:
- Utilizing the density functional dynamical mean-field theory (DFDMFT) scheme.
- Applying local-density approximation plus dynamical mean-field theory (LDA+DMFT).
Main Results:
- Mackinawite shows proximity to selective Mott localization.
- Coexistence of pseudogapped and anisotropic Dirac-like electronic dispersion observed at the Mott transition border.
- Demonstrated dual semiconducting and metallic responses in tetragonal FeS.
Conclusions:
- Findings provide a new understanding of many-particle physics in quantum materials with coexisting Dirac-fermions and pseudogapped electronic states.
- Propose that electron-doped FeS, tuned towards a metallic regime, may exhibit unconventional superconductivity.
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