Orbital Selective Mott Transition Effects and Non-Trivial Topology of Iron Chalcogenide

Abstract

The iron-based superconductor FeSe${}_{1-x}$Te${}_x$ (FST) has recently gained significant attention as a host of two distinct physical phenomena: ($i$) Majorana zero modes which can serve as potential topologically protected qubits, and ($ii$) a realization of the orbital selective Mott transition (OSMT). In this Letter, we connect these two phenomena and provide new insights into the interplay between strong electronic correlations and non-trivial topology in FST. Using linearized quasiparticle self-consistent GW plus dynamical mean-field theory, we show that the topologically protected Dirac surface state has substantial Fe($d_{xy}$) character. The proximity to the OSMT plays a dual role, it facilitates the appearance of the topological surface state by bringing the Dirac cone close to the chemical potential, but destroys the Z${}_2$ topological superconductivity when the system is too close to the orbital selective Mott phase (OSMP). We derive a reduced effective Hamiltonian that describes the topological band. Its parameters capture all the chemical trends found in the first principles calculation. Our findings provide a framework for further study of the interplay between strong electronic correlations and non-trivial topology in other iron-based superconductors.

5 pages, 4 figures, and supplemental material

References in corpus (16)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Superconductivity close to magnetic instability in Fe(Se1-xTex)0.82
• Quantum Monte Carlo Impurity Solver for Cluster DMFT and Electronic Structure Calculations in Adjustable Base
• Tellurium substitution effect on superconductivity of the alpha-phase Iron Selenide
• First-order magnetic and structural phase transitions in Fe${}_{1+y}$Se${}_x$Te${}_{1-x}$
• Bulk Superconductivity at 14 K in Single Crystals of Fe1+yTexSe1-x
• Ironing out the details of unconventional superconductivity
• Fractional power-law behavior and its origin in iron-chalcogenide and ruthenate superconductors: Insights from first-principles calculations
• Ordered and tunable Majorana-zero-mode lattice in naturally strained LiFeAs
• FeTe as a candidate material for new iron-based superconductor
• Neutron scattering Measurements of the phonon density of states of FeSe${}_{1-x}$ superconductors
• Correlation-Driven Electronic Reconstruction in FeTe${}_{1-x}$Se${}_x$
• Orbital-selective Mott phase in multiorbital models for iron pnictides and chalcogenides
• On the interplay of paramagnetism and topology in the Fe-based High Tc Superconductors
• Revealing the Origin of Time-reversal Symmetry Breaking in Fe-chalcogenide Superconductor FeTe1-xSex
• Correlation-corrected band topology and topological surface states in iron-based superconductors

Cited by in corpus (12)

• Can Orbital-Selective Néel Transitions Survive Strong Nonlocal Electronic Correlations?
• Universal Superconductivity in FeTe and All-Iron-Based Ferromagnetic Superconductor Heterostructures
• LiV2O4: Hund-Assisted Orbital-Selective Mottness
• Strong-coupling high-$T_{\mathrm{c}}$ superconductivity in doped correlated band insulators
• Low-energy interband Kondo bound states in orbital-selective Mott phases
• Fragility of Topology under Electronic Correlations in Iron Chalcogenides
• Photomagnetic-Chiral Anisotropy mediated by Chirality-Driven Asymmetric Spin Splitting
• Evolution of the intertwining correlated topological phases in iron-based superconductor Fe(Te,Se)
• Orbital-Selective Spin-Orbit Mott Insulator in Fractional Valence Iridate La${}_3$Ir${}_3$O${}_{11}$
• Hund's coupling assisted orbital-selective superconductivity in Ba1-xKxFe2As2
• Symmetry-breaking-induced topology in FeSe
• Layer controlled orbital selective Mott transition in monolayer nickelate