Quantum Criticality in the 122 Iron Pnictide Superconductors Emerging from Orbital-Selective Mottness

Abstract

The twin issues of the nature of the normal state and competing order(s) in the iron arsenides are central to understanding their unconventional, high-Tc superconductivity. We use a combination of transport anisotropy measurements on detwinned Sr(Fe(1-x)Co(x))2As2 single crystals and local density approximation plus dynamical mean field theory (LDA + DMFT) calculations to revisit these issues. The peculiar resistivity anisotropy and its evolution with x are naturally interpreted in terms of an underlying orbital-selective Mott transition (OSMT) that gaps out the dxz or dyz states. Further, we use a Landau-Ginzburg approach using LDA + DMFT input to rationalize a wide range of anomalies seen up to optimal doping, providing strong evidence for secondary electronic nematic order. These findings suggest that strong dynamical fluctuations linked to a marginal quantum-critical point associated with this OSMT and a secondary electronic nematic order constitute an intrinsically electronic pairing mechanism for superconductivity in Fe arsenides.

9 pages, revtex4-1, published version

References in corpus (11)

• Evidence for an electron nematic phase transition in underdoped iron pnictide superconductors
• Fractionalized Fermi liquids
• Nematic and meta-nematic transitions in the iron pnictides
• Quantum Criticality
• Magnetism and Charge Dynamics in Iron Pnictides
• Orbital-selective Mott Phase in Multiorbital Models for Alkaline Iron Selenides K(1-x)Fe(2-y)Se2
• Quantum and Topological Criticalities of Lifshitz Transition in Two-Dimensional Correlated Electron Systems
• Electron doping evolution of the anisotropic spin excitations in BaFe2-xNixAs2
• Multisite versus multiorbital Coulomb correlations studied within finite-temperature exact diagonalization dynamical mean-field theory
• Electronic structure and effects of dynamical electron correlation in ferromagnetic bcc-Fe, fcc-Ni and antiferromagnetic NiO
• Quantum Criticality out of Equilibrium: Steady State in a Magnetic Single-Electron Transistor

Cited by in corpus (9)

• Orbital selectivity enhanced by nematic order in FeSe
• Impact of Uniaxial Pressure on Structural and Magnetic Phase Transitions in Electron-Doped Iron Pnictides
• Orbital selective spin excitations and their impact on superconductivity of LiFe1-xCoxAs
• Impact of the first order antiferromagnetic phase transition on the paramagnetic spin excitations and nematic phase of SrFe${}_2$As${}_2$
• Do Dynamical Excitonic Liquid Correlations Mediate Superconductivity in Elemental Bismuth?
• A DMFT+CTQMC Investigation of Strange Metallicity in Local Quantum Critical Scenario
• Evidences for local non-centrosymmetricity and strong phonon anomaly in EuCu2As2: A Raman spectroscopy and lattice dynamics study
• Temperature and doping dependence of normal state spectral properties in a two-orbital model for ferropnictides
• Microscopic Description of Unconventional Nodal Superconductivity in FeSe