Magnetic order without tetragonal-symmetry-breaking in iron arsenides: microscopic mechanism and spin-wave spectrum

Abstract

Most iron-based superconductors undergo a transition to a magnetically ordered state characterized by staggered stripes of parallel spins. With ordering vectors $(\pi ,0)$ or $(0,\pi )$, this magnetic state breaks the high-temperature tetragonal symmetry of the system, which is manifested by a splitting of the lattice Bragg peaks. Remarkably, recent experiments in hole-doped iron arsenides reported an ordered state that displays magnetic Bragg peaks at $(\pi ,0)$ and $(0,\pi )$ but remains tetragonal. Despite being inconsistent with a magnetic stripe configuration, this unusual magnetic phase can be described in terms of a double-$\mathbf{Q}$ magnetic structure consisting of an equal-weight superposition of the ordering vectors $(\pi ,0)$ and $(0,\pi )$. Here we show that a non-collinear double-$\mathbf{Q}$ magnetic configuration, dubbed \emph{orthomagnetic}, arises naturally within an itinerant three-band microscopic model for the iron pnictides. In particular, we find that strong deviations from perfect nesting and residual interactions between the electron pockets favor the orthomagnetic over the stripe magnetic state. Using an effective low-energy model, we also calculate the spin-wave spectrum of the orthomagnetic state. In contrast to the stripe state, there are three Goldstone modes, manifested in all diagonal and one off-diagonal component of the spin-spin correlation function. The total magnetic structure factor displays two anisotropic spin-wave branches emerging from both $(\pi ,0)$ and $(0,\pi )$ momenta, in contrast to the case of domains of stripe order, where only one spin-wave branch emerges from each momentum. We propose that these unique features of the orthomagnetic state can be used to unambiguously distinguish it from the stripe state via neutron scattering experiments, and discuss the implications of its existence to the nature of the magnetism of the iron arsenides.

arXiv comment12 pages, 7 figures

References in corpus (42)

• The Puzzle of High Temperature Superconductivity in Layered Iron Pnictides and Chalcogenides
• High-temperature superconductivity in iron-based materials
• Nematic order in iron superconductors - who is in the driver's seat?
• Magnetism, superconductivity, and pairing symmetry in Fe-based superconductors
• To What Extent Iron-Pnictide New Superconductors Have Been Clarified: A Progress Report
• Theory of Electron Nematic Order in LaOFeAs
• Magnetism and its microscopic origin in iron-based high-temperature superconductors
• Ising and Spin orders in Iron-based Superconductors
• FeAs-based superconductivity: a case study of the effects of transition metal doping on BaFe2As2
• Spin Waves and Magnetic Exchange Interactions in CaFe2As2
• Ferro-Orbital Order and Strong Magnetic Anisotropy in the Parent Compounds of Iron-Pnictide Superconductors
• Preemptive nematic order, pseudogap, and orbital order in the iron pnictides
• Origin of the spin density wave instability in AFe${}_2$As${}_2$ (A=Ba, Sr) as revealed by optical spectroscopy
• Orbital-Ordering Induces Structural Phase Transition and the Resistivity Anomaly in Iron Pnictides
• Nematic spin fluid in the tetragonal phase of BaFe2As2
• Nematic spin correlations in the tetragonal state of uniaxial strained BaFe2-xNixAs2
• Magnetically-Driven Suppression of Nematic Order in an Iron-Based Superconductor
• Microscopic origin of magnetism and magnetic interactions in ferropnictides
• Magnetic degeneracy and hidden metallicity of the spin density wave state in ferropnictides
• Theory of itinerant magnetic excitations in the SDW phase of iron-based superconductors
• Competing orders in FeAs layers
• Antiferromagnetic ordering in the absence of a structural distortion in Ba(Fe{1-x}Mn{x})2As2
• Renormalization group flow, competing phases, and the structure of superconducting gap in multi-band models of Iron based superconductors
• Proximity of Iron Pnictide Superconductors to a Quantum Tricritical Point
• Ultrafast observation of critical nematic fluctuations and giant magnetoelastic coupling in iron pnictides
• Magnetic Excitations in the High Tc Iron Pnictides
• Spin Rotation Technique for Non-Collinear Magnetic Systems: Application to the Generalized Villain Model
• Spin Waves in Striped Phases
• New Phase Induced by Pressure in the Iron-Arsenide Superconductor K-Ba122
• In-plane anisotropy of electrical resistivity in the strain-detwinned SrFe2As2
• Microscopically derived Ginzburg-Landau theory for magnetic order in the iron pnictides
• Possible realization of an antiferromagnetic Griffiths phase in Ba[Fe(1-x)Mn(x)](2)As(2)
• Enhancing magnetic stripe order in iron pnictides by RKKY exchange interactions
• Multiorbital Spin Susceptibility in a Magnetically Ordered State - Orbital versus Excitonic Spin Density Wave Scenario
• Dimensional crossover in the quasi-two-dimensional Ising-O(3) model
• Spin-waves in the $J_{1a}-J_{1b}-J_2$ orthorombic square-lattice Heisenberg models: Application to the iron pnictide materials
• Phase transitions in spin-orbital models with spin-space anisotropies for iron-pnictides: A study through Monte Carlo simulations
• Magnetic structure and critical behavior of GdRhIn${}_5$: resonant x-ray diffraction and renormalization group analysis
• Properties of a diagonal 2-orbital ladder model of the Fe-pnictide superconductors
• Impact of local-moment fluctuations on the magnetic degeneracy of iron arsenide superconductors
• Antiferromagnetism in Iron-Based Superconductors: Selection of Magnetic Order and Quasiparticle Interference
• Magnetic ordering in GdNi2B2C revisited by resonant x-ray scattering: evidence for the double-q model

Cited by in corpus (34)

• Intertwined vestigial order in quantum materials: nematicity and beyond
• Superconductivity-induced reentrance of orthorhombic distortion in Ba1-xKxFe2As2
• Low-energy microscopic models for iron-based superconductors: a review
• Double-Q spin-density wave in iron arsenide superconductors
• Hedgehog spin-vortex crystal stabilized in a hole-doped iron-based superconductor
• Spin fluctuations in iron pnictides and chalcogenides: From antiferromagnetism to superconductivity
• Magnetic interactions in iron superconductors: A review
• Competing magnetic double-Q phases and superconductivity-induced re-entrance of C2 magnetic stripe order in iron pnictides
• Vestigial chiral and charge orders from bidirectional spin-density waves: Application to the iron-based superconductors
• Spin reorientation driven by the interplay between spin-orbit coupling and Hund's rule coupling in iron pnictides
• Detailed magnetic and structural analysis mapping a robust magnetic C4 dome in Sr1-xNaxFe2As2
• Local orthorhombicity in the magnetic $C_4$ phase of the hole-doped iron-arsenide superconductor Sr${}_{1-x}$Na${}_x$Fe${}_2$As${}_2$
• Disorder-promoted $C_4$-symmetric magnetic order in iron-based superconductors
• Muon-spin-rotation study of the magnetic structure in the tetragonal antiferromagnetic state of weakly underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Spin-Driven Nematic Instability of the Multi-Orbital Hubbard Model: Application to Iron-Based Superconductors
• Antiferromagnetic order in CaK(Fe[1-x]Ni[x])4As4 and its interplay with superconductivity
• Infrared study of the spin reorientation transition and its reversal in the superconducting state in underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Topological Superconductivity Induced by Magnetic Texture Crystals
• Unravelling incommensurate magnetism and its emergence in iron-based superconductors
• Spin excitations in the nematic phase and the metallic stripe spin-density wave phase of iron pnictides
• Expansion of the tetragonal magnetic phase with pressure in the iron-arsenide superconductor Ba{1-x}KxFe2As2
• Role of multiorbital effects in the magnetic phase diagram of iron-pnictides
• Emergent magnetic degeneracy in iron pnictides due to the interplay between spin-orbit coupling and quantum fluctuations
• Spin and quadrupolar orders in the spin-1 bilinear-biquadratic model for iron-based superconductors
• 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
• Collective magnetic excitations of $C_4$ symmetric magnetic states in iron-based superconductors
• Raman resonance in iron-based superconductors: The magnetic scenario
• Damped spin-wave excitations in the itinerant antiferromagnet $\gamma$-Fe${}_{0.7}$Mn${}_{0.3}$
• Antiferromagnetic chiral spin density wave and strain-induced Chern insulator in the square lattice Hubbard model with frustration
• Scaling of the Fano effect of the in-plane Fe-As phonon and the superconducting critical temperature in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Inversion-asymmetric itinerant antiferromagnets by the space group symmetry
• Anisotropic superconductivity and Fermi surface reconstruction in the spin-vortex antiferromagnetic superconductor CaK(Fe${}_{0.95}$Ni${}_{0.05}$)${}_4$As${}_4$
• Emergence of novel magnetic order at finite temperature in overdoped pnictides