Mott transition in Modulated Lattices and Parent Insulator of (K,Tl)yFexSe2 Superconductors
arXiv:1101.3307 · doi:10.1103/PhysRevLett.106.186401
Abstract
The degree of electron correlations remains a central issue in the iron-based superconductors. The parent iron pnictides are antiferromagnetic, and their bad-metal behavior has been interpreted in terms of proximity to a Mott transition. We study such a transition in multi-orbital models on modulated lattices containing an ordered pattern of iron vacancies, using a slave-rotor method. We show that the ordered vacancies lead to a band-narrowing, which pushes the system to the Mott insulator side. This effect is proposed to underlie the insulating behavior observed in the parent compounds of the newly discovered (K,Tl)yFexSe2 superconductors.
4 pages, 4 figures, revised version. To appear in PRL
References in corpus (13)
- Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
- Near-degeneracy of several pairing channels in multiorbital models for the Fe-pnictides
- Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
- A minimal two-band model for the superconducting Fe-pnictides
- Heavily electron-doped electronic structure and isotropic superconducting gap in AxFe2Se2 (A=K,Cs)
- Fe-based high temperature superconductivity with Tc=31K bordering an insulating antiferromagnet in (Tl,K)FexSe2 Crystals
- Origin of the spin density wave instability in AFeAs (A=Ba, Sr) as revealed by optical spectroscopy
- Orbital selective Mott transition in multi-band systems: slave-spin representation and dynamical mean-field theory
- Correlation effects in the iron pnictides
- Signatures of Electronic Correlations in Optical Properties of LaFeAsOF
- Self-consistent slave rotor mean field theory for strongly correlated systems
- Electronic Structure, Topological Phase Transitions and Superconductivity in (K,Cs)xFe2Se2
- Density Functional Study of the Over-Doped Iron Chalcogenide: TlFeSe with ThCrSi structure