Infrared study of the spin reorientation transition and its reversal in the superconducting state in underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$

Abstract

With infrared spectroscopy we investigated the spin-reorientation transition from an orthorhombic antiferromagnetic (o-AF) to a tetragonal AF (t-AF) phase and the reentrance of the o-AF phase in the superconducting state of underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$. In agreement with the predicted transition from a single-$\mathbf{Q}$ to a double-$\mathbf{Q}$ AF structure, we found that a distinct spin density wave (SDW) develops in the t-AF phase. The pair breaking peak of this SDW acquires much more low-energy spectral weight than the one in the o-AF state which indicates that it competes more strongly with superconductivity. We also observed additional phonon modes in the t-AF phase which likely arise from a Brillouin-zone folding that is induced by the double-$\mathbf{Q}$ magnetic structure with two Fe sublattices exhibiting different magnitudes of the magnetic moment.

Supplementary information included

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Cited by in corpus (25)

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• Competing magnetic double-Q phases and superconductivity-induced re-entrance of C2 magnetic stripe order in iron pnictides
• Spin reorientation driven by the interplay between spin-orbit coupling and Hund's rule coupling in iron pnictides
• Muon-spin-rotation study of the magnetic structure in the tetragonal antiferromagnetic state of weakly underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Topological Superconductivity Induced by Magnetic Texture Crystals
• Unravelling incommensurate magnetism and its emergence in iron-based superconductors
• Expansion of the tetragonal magnetic phase with pressure in the iron-arsenide superconductor Ba{1-x}KxFe2As2
• Emergent magnetic degeneracy in iron pnictides due to the interplay between spin-orbit coupling and quantum fluctuations
• Role of multiorbital effects in the magnetic phase diagram of iron-pnictides
• Spin-Orbit Coupling and Magnetic Anisotropy in 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
• Muon spin rotation and infrared spectroscopy study of magnetism and superconductivity in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Anomalous Composition-Induced Crossover in the Magnetic Properties of the Itinerant-Electron Antiferromagnet Ca{1-x}Sr{x}Co{2-y}As{2}
• Competing Electronic Phases near the Onset of Superconductivity in Hole-doped SrFe2As2
• Spectral Evidence for Emergent Order in Ba${}_{1-x}$Na${}_x$Fe${}_2$As${}_2$
• Muon spin rotation and infrared spectroscopy study of $B{a}_{1-x}N{a}_{x}F{e}_{2}A{s}_2$
• Scanning tunneling spectroscopy as a probe of multi-Q magnetic states of itinerant magnets
• Trapping Majorana Zero Modes in Vortices of Magnetic Texture Crystals Coupled to Nodal Superconductors
• Strong Spin Resonance Mode associated with suppression of soft magnetic ordering in Hole-doped Ba1-xNaxFe2As2
• 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${}_2$
• Dependence of the absolute value of the penetration depth in $(\mathbf{B}{\mathbf{a}}_{1-\mathbf{x}}{\mathbf{K}}_{\mathbf{x}})\mathbf{F}{\mathbf{e}}_2\mathbf{A}{\mathbf{s}}_2$ on doping
• Optical and photoemission investigation of structural and magnetic transitions in the iron-based superconductor Sr${}_{0.67}$Na${}_{0.33}$Fe${}_2$As${}_2$
• Raman scattering study of tetragonal magnetic phase in Sr${}_{1-x}$Na${}_x$Fe${}_2$As${}_2$: structural symmetry and electronic gap
• Infrared spectroscopy study of the in-plane response of YBa2Cu3O6.6 in magnetic fields up to 30 Tesla