The magnetic phase diagram of an extended J1-J2 model on a modulated square lattice and its implications for the antiferromagnetic phase of KyFexSe2

Abstract

Motivated by the experimentally observed $\sqrt{5}\times \sqrt{5}$ iron vacancy order and a block spin antiferromagnetic phase with large magnetic moment in ${\mathrm{K}}_{0.8}{\mathrm{Fe}}_{1.6}{\mathrm{Se}}_2$, we study the magnetic phase diagram of an extended $J_1-J_2$ model on a 1/5-depleted square lattice with $\sqrt{5}\times \sqrt{5}$ vacancy order, using a classical Monte Carlo analysis. The magnetic phase diagram involves various antiferromagnetically ordered phases, and most of them have higher order commensuration. We find that the experimentally relevant block-spin state occupies a significant portion of the phase diagram, and we discuss the spin dynamics of this phase using a linear spin-wave analysis. Based on our spin wave calculations in different parameter regimes corresponding to the block spin antiferromagnetic phase, we show how spin-wave degeneracy along the high symmetry directions of the magnetic Brillouin zone can provide information regarding the underlying exchange couplings. We have also analyzed the magnetic phase diagram of a $J_1-J_2$ model on two different modulated square lattices relevant for ${\mathrm{K}}_y{\mathrm{Fe}}_{1.5}{\mathrm{Se}}_2$, which respectively exhibit 1/4-depleted $2\times 2$ and $4\times 2$ vacancy ordering.

9 pages, 8 figures, 3 tables

References in corpus (21)

• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
• Competing Orders and Spin-Density-Wave Instability in La(O${}_{1-x}$F${}_x$)FeAs
• Heavily electron-doped electronic structure and isotropic superconducting gap in AxFe2Se2 (A=K,Cs)
• Fe-based high temperature superconductivity with Tc=31K bordering an insulating antiferromagnet in (Tl,K)FexSe2 Crystals
• A Novel Large Moment Antiferromagnetic Order in K0.8Fe1.6Se2 Superconductor
• Bi-collinear antiferromagnetic order in the tetragonal $\alpha$-FeTe
• Origin of the spin density wave instability in AFe${}_2$As${}_2$ (A=Ba, Sr) as revealed by optical spectroscopy
• Common Crystalline and Magnetic Structure of superconducting A2Fe4Se5
• Distinct Fermi Surface Topology and Nodeless Superconducting Gap in (Tl0.58Rb0.42)Fe1.72Se2 Superconductor
• Iron pnictides as a new setting for quantum criticality
• Transport properties of the new Fe-based superconductor KxFe2Se2 (Tc = 33 K)
• Spin waves in the $(\pi ,0)$ magnetically ordered iron chalcogenide Fe${}_{1.05}$Te
• Ternary iron selenide K${}_{0.8}$Fe${}_{1.6}$Se${}_2$ is an antiferromagnetic semiconductor
• Mott transition in Modulated Lattices and Parent Insulator of (K,Tl)yFexSe2 Superconductors
• Block Spin Ground State and 3-Dimensionality of (K,Tl)Fe${}_{1.6}$Se${}_2$
• Correlation effects in the iron pnictides
• Signatures of Electronic Correlations in Optical Properties of LaFeAsO${}_{1-x}$F${}_x$
• Electronic and magnetic structures of ternary iron selenides AFe${}_2$Se${}_2$ (A=K, Cs, or Tl)
• Density Functional Study of the Over-Doped Iron Chalcogenide: TlFe${}_2$Se${}_2$ with ThCr${}_2$Si${}_2$ structure
• The spin excitations of the block-antiferromagnetic K${}_{0.8}$Fe${}_{1.6}$Se${}_2$

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• The Unexpected Properties of Alkali Metal Iron Selenide Superconductors
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• Spin Waves and magnetic exchange interactions in insulating Rb${}_{0.89}$Fe${}_{1.58}$Se${}_2$
• New ternary ThCr2Si2-type iron-selenide superconducting materials: synthesis, properties and simulations
• Superconductivity at the Border of Electron Localization and Itinerancy
• Spin dynamics of the block orbital-selective Mott phase
• Novel Magnetic Block States in Low-Dimensional Iron-Based Superconductors
• Structural, Magnetic and Electronic Properties of the Iron-Chalcogenide A${}_x$Fe${}_{2-y}$Se${}_2$ (A=K, Cs, Rb, Tl and etc.) Superconductors
• Block Antiferromagnetism and Checkerboard Charge Ordering in Alkali-doped Iron Selenides $R$${}_{1-x}$Fe${}_{2-y}$Se${}_2$
• Spin reorientation in TlFe1.6Se2 with complete vacancy ordering
• Magnetic Frustration and Iron-Vacancy Ordering in Iron-Chalcogenide
• Block orbital-selective Mott insulators: a spin excitation analysis
• Anticollinear magnetic order induced by impurities in the frustrated Heisenberg model of pnictides
• Vacancy Driven Orbital and Magnetic Order in (K,Tl,Cs)${}_y$Fe${}_{2-x}$Se${}_2$
• Study of the magnetic state of K${}_{0.8}$Fe${}_{1.6}$Se${}_2$ using the five-orbital Hubbard model in the Hartree-Fock approximation
• Neutron Scattering Study on Spin Dynamics in Superconducting (Tl,Rb)2Fe4Se5
• Quantum magnetism of iron-based ladders: Blocks, spirals, and spin flux
• Evolution of the nuclear and magnetic structures of TlFe1.6Se2 with temperature
• Electron Correlation and Spin Dynamics in Iron Pnictides and Chalcogenides
• Two-Fluid Description for Iron-Based Superconductors
• Block antiferromagnetism and possible ferroelectricity in KFe${}_2$Se${}_2$
• Dynamic approach to finite-temperature magnetic phase transitions in the extended J1- J2 model with vacancy order
• Emergence of novel magnetic order at finite temperature in overdoped pnictides
• Spin triplet pairing by suppressing altermagnetism