Spin-orbital interplay and topology in the nematic phase of iron pnictides

Abstract

The origin of the nematic state is an important puzzle to be solved in iron pnictides. Iron superconductors are multiorbital systems and these orbitals play an important role at low energy. The singular $C_4$ symmetry of $d_{zx}$ and $d_{yz}$ orbitals has a profound influence at the Fermi surface since the $\Gamma$ pocket has vortex structure in the orbital space and the X/Y electron pockets have $yz$/$zx$ components respectively. We propose a low energy theory for the spin--nematic model derived from a multiorbital Hamiltonian. In the standard spin--nematic scenario the ellipticity of the electron pockets is a necessary condition for nematicity. In the present model nematicity is essentially due to the singular $C_4$ symmetry of $yz$ and $zx$ orbitals. By analyzing the ($\pi ,0$) spin susceptibility in the nematic phase we find spontaneous generation of orbital splitting extending previous calculations in the magnetic phase. We also find that the ($\pi ,0$) spin susceptibility has an intrinsic anisotropic momentum dependence due to the non trivial topology of the $\Gamma$ pocket.

10 pages (main text + 2 appendices), 3 figures, final version

References in corpus (28)

• 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
• Theory of Electron Nematic Order in LaOFeAs
• Ising and Spin orders in Iron-based Superconductors
• Nematic and meta-nematic transitions in the iron pnictides
• Orbital-driven nematicity in FeSe
• Magnetism and Charge Dynamics in Iron Pnictides
• Nodal Spin Density Wave and band topology of the FeAs based materials
• Orbital Order and Spontaneous Orthorhombicity in Iron Pnictides
• Nematic spin correlations in the tetragonal state of uniaxial strained BaFe2-xNixAs2
• Unprecedented anisotropic metallic state in BaFe2As2 revealed by optical spectroscopy
• Manifestations of nematic degrees of freedom in the magnetic, elastic, and superconducting properties of the iron pnictides
• 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
• Competing orders in FeAs layers
• Conductivity anisotropy in the antiferromagnetic state of iron pnictides
• Low magnetization and anisotropy in the antiferromagnetic state of undoped iron pnictides
• Effect of Co doping on the in-plane anisotropy in the optical spectrum of underdoped Ba(Fe1-xCox)2As2
• Magnetic and Metallic State at Intermediate Hubbard U Coupling in Multiorbital Models for Undoped Fe Pnictides
• Thermopower as sensitive probe of electronic nematicity in iron pnictides
• Emergent defect states as a source of resistivity anisotropy in the nematic phase of iron pnictides
• Theory of fluctuation conductivity from interband pairing in pnictide superconductors
• Magnetic excitations in underdoped Ba(Fe1-xCox)2As2 with x=0.047
• Effect of the tetrahedral distortion on the electronic properties of iron-pnictides
• Effects of Lifshitz Transition on Charge Transport in Magnetic Phases of Fe-Based Superconductors
• Crystal Symmetry and Magnetic Order in Iron Pnictides: a Tight Binding Wannier Function Analysis
• Diverging Nematic Susceptibility, Physical Meaning of T* scale, and Pseudogap in the Spin Fermion Model for Pnictides
• Anisotropic inplane spin correlation in the parent and Co-doped BaFe2As2: a neutron scattering study

Cited by in corpus (10)

• Low-energy microscopic models for iron-based superconductors: a review
• Intertwined spin-orbital coupled orders in the iron-based superconductors
• Nematic Fluctuations in an Orbital Selective Superconductor Fe${}_{1+y}$Te${}_{1-x}$Se${}_x$
• Potential Lifshitz transition at optimal substitution in nematic pnictide Ba${}_{1-x}$Sr${}_x$Ni${}_2$As${}_2$
• Electronic origin of structural transition in 122 Fe based superconductors
• Theory of spin-excitation anisotropy in the nematic phase of FeSe obtained from RIXS measurements
• Theories for charge-driven nematicity in kagome metals
• The role of orbital nesting in the superconductivity of Iron-based Superconductors
• Feedback of non-local $d_{xy}$ nematicity on the magnetic anisotropy in FeSe
• Resistivity anisotropy from the multiorbital Boltzmann equation in nematic FeSe