Emergent magnetic degeneracy in iron pnictides due to the interplay between spin-orbit coupling and quantum fluctuations

Abstract

Recent experiments in iron pnictide superconductors reveal that, as the putative magnetic quantum critical point is approached, different types of magnetic order coexist over a narrow region of the phase diagram. Although these magnetic configurations share the same wave-vectors, they break distinct symmetries of the lattice. Importantly, the highest superconducting transition temperature takes place close to this proliferation of near-degenerate magnetic states. In this paper, we employ a renormalization group calculation to show that such a behavior naturally arises due to the effects of spin-orbit coupling on the quantum magnetic fluctuations. Formally, the enhanced magnetic degeneracy near the quantum critical point is manifested as a stable Gaussian fixed point with a large basin of attraction. Implications of our findings to the superconductivity of the iron pnictides are also discussed.

6 pages, 2 figures, published version

References in corpus (17)

• High-temperature superconductivity in iron-based materials
• Magnetism and its microscopic origin in iron-based high-temperature superconductors
• Hedgehog spin-vortex crystal stabilized in a hole-doped iron-based superconductor
• Competing orders in FeAs layers
• Antiferromagnetic ordering in the absence of a structural distortion in Ba(Fe{1-x}Mn{x})2As2
• Spin reorientation in Na-doped BaFe${}_2$As${}_2$ studied by neutron diffraction
• New Phase Induced by Pressure in the Iron-Arsenide Superconductor K-Ba122
• Suppression of superconductivity by Neel-type magnetic fluctuations in the iron pnictides
• Anisotropic Neutron Spin Resonance in Superconducting BaFe${}_{1.9}$Ni${}_{0.1}$As${}_2$
• Uniaxial strain control of spin-polarization in multicomponent nematic order of BaFe${}_2$As${}_2$
• Magnetic order without tetragonal-symmetry-breaking in iron arsenides: microscopic mechanism and spin-wave spectrum
• Local orthorhombicity in the magnetic $C_4$ phase of the hole-doped iron-arsenide superconductor Sr${}_{1-x}$Na${}_x$Fe${}_2$As${}_2$
• Symmetry of re-entrant tetragonal phase in Ba1-xNaxFe2As2: Magnetic versus orbital ordering mechanism
• Role of multiorbital effects in the magnetic phase diagram of iron-pnictides
• Magnetic phase diagram of the iron pnictides in the presence of spin-orbit coupling: Frustration between $C_2$ and $C_4$ magnetic phases
• Order parameter fluctuation and ordering competition in $\mathrm{B}{\mathrm{a}}_{1-\mathrm{x}}{\mathrm{K}}_{\mathrm{x}}\mathrm{F}{\mathrm{e}}_2\mathrm{A}{\mathrm{s}}_2$
• Non-trivial role of interlayer cation states in iron-based superconductors

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• Symmetry breaking and ascending in the magnetic kagome metal FeGe
• Widespread orthorhombic fluctuations in the (Sr,Na)Fe${}_2$As${}_2$ family of superconductors
• Cascade of vestigial orders in two-component superconductors: nematic, ferromagnetic, s-wave charge-4e, and d-wave charge-4e states
• Magnetic phase diagram of the iron pnictides in the presence of spin-orbit coupling: Frustration between $C_2$ and $C_4$ magnetic phases
• Intertwined spin-orbital coupled orders in the iron-based superconductors
• Competing Electronic Phases near the Onset of Superconductivity in Hole-doped SrFe2As2
• Muon spin rotation and infrared spectroscopy study of $B{a}_{1-x}N{a}_{x}F{e}_{2}A{s}_2$
• Pressure-Induced Large Volume Collapse, Plane-to-Chain, Insulator to Metal Transition in CaMn${}_2$Bi${}_2$
• Preferred magnetic excitations in Sr${}_{1-x}$Na${}_x$Fe${}_2$As${}_2$
• Competition between orthorhombic and re-entrant tetragonal phases in underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$ probed by the response to controlled disorder
• Zero-point quantum swing of magnetic couples