Spin Dynamics of a $J_1-J_2$ Antiferromagnet and its Implications for Iron Pnictides

Abstract

Motivated by the recent observation of antiferromagnetic correlations in the paramagnetic phase of iron pnictides, we study the finite-temperature spin dynamics of a two-dimensional $J_1-J_2$ antiferromagnet. We consider the paramagnetic phase in the $J_2>J_1$ regime of a $(\pi ,0)$ collinear ground state, using the modified spin wave theory. Below the mean-field Ising transition temperature, we identify short-range anisotropic antiferromagnetic correlations. We show that the dynamical structure factor $\mathcal{S}(\mathbf{q},\omega )$ contains elliptic features in the momentum space, and determine its variation with temperature and energy. Implications for the spin-dynamical experiments in the iron pnictides are discussed.

11 pages, 7 figures, replaced with the version published in Phys. Rev. B

References in corpus (24)

• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• Evidence for an electron nematic phase transition in underdoped iron pnictide superconductors
• Near-degeneracy of several pairing channels in multiorbital models for the Fe-pnictides
• Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
• Theory of Electron Nematic Order in LaOFeAs
• Symmetry breaking orbital anisotropy on detwinned Ba(Fe1-xCox)2As2 above the spin density wave transition
• Origin of the ~150 K Anomaly in LaOFeAs; Competing Antiferromagnetic Superexchange Interactions, Frustration, and Structural Phase Transition
• Correlated electronic structure of LaOFeAs
• Ising and Spin orders in Iron-based Superconductors
• Fe-based high temperature superconductivity with Tc=31K bordering an insulating antiferromagnet in (Tl,K)FexSe2 Crystals
• Spin-orbital frustrations and anomalous metallic state in iron-pnictide superconductors
• Origin of the spin density wave instability in AFe${}_2$As${}_2$ (A=Ba, Sr) as revealed by optical spectroscopy
• Nodal Spin Density Wave and band topology of the FeAs based materials
• Antiferromagnetic superexchange interactions in LaOFeAs
• Nematic spin fluid in the tetragonal phase of BaFe2As2
• Iron pnictides as a new setting for quantum criticality
• Symmetry of spin excitation spectra in the tetragonal paramagnetic and superconducting phases of 122-ferropnictides
• Theory of itinerant magnetic excitations in the SDW phase of iron-based superconductors
• Itinerant Spin Excitations in SrFe2As2 Measured by Inelastic Neutron Scattering
• Correlation effects in the iron pnictides
• Pnictides as frustrated quantum antiferromagnet close to a quantum phase transition
• Signatures of Electronic Correlations in Optical Properties of LaFeAsO${}_{1-x}$F${}_x$
• Symplectic N and time reversal in frustrated magnetism
• Three dimensional generalization of the $J_1$-$J_2$ Heisenberg model on a square lattice and role of the interlayer coupling $J_c$

Cited by in corpus (21)

• Superconductivity in Iron Compounds
• Nematic order in iron superconductors - who is in the driver's seat?
• Manifestations of nematic degrees of freedom in the magnetic, elastic, and superconducting properties of the iron pnictides
• Orbital selective Fermi surface shifts and mechanism of high T${}_c$ superconductivity in correlated AFeAs (A=Li,Na)
• Competition between stripe and checkerboard magnetic instabilities in Mn-doped BaFe2As2
• Spin Dynamics of a J1-J2-K Model for the Paramagnetic Phase of Iron Pnictides
• RVB superconductors with fermionic projected entangled pair states
• Magnetic excitations in underdoped Ba(Fe1-xCox)2As2 with x=0.047
• Spin excitations in the nematic phase and the metallic stripe spin-density wave phase of iron pnictides
• Nematicity from mixed S_{+-} + d_{x^2-y^2} states in iron-based superconductors
• Neutron Scattering Measurements of Spatially Anisotropic Magnetic Exchange Interactions in Semiconducting K0.85Fe1.54Se2 (TN=280 K)
• Spin and quadrupolar orders in the spin-1 bilinear-biquadratic model for iron-based superconductors
• Giant biquadratic interaction induced magnetic anisotropy in the iron-based superconductor AxFe2-ySe2
• Spectrum splitting of bimagnon excitations in a spatially frustrated Heisenberg antiferromagnet revealed by resonant inelastic x-ray scattering
• Ising-nematic order in the bilinear-biquadratic model for the iron pnictides
• Magnon-phonon coupling effects on the indirect K-edge resonant inelastic X-ray scattering spectrum of a 2D Heisenberg antiferromagnet
• High-Energy Damping by Particle-Hole Excitations in the Spin-Wave Spectrum of Iron-Based Superconductors
• Electron Correlation and Spin Dynamics in Iron Pnictides and Chalcogenides
• Magnetic and Ising quantum phase transitions in a model for isoelectronically tuned iron pnictides
• Anisotropic magnetic excitations of a frustrated bilinear-biquadratic spin model -- Implications for spin waves of detwinned iron pnictides
• Detecting Crystallographic Lattice Chirality using Resonant Inelastic X-ray Scattering