Two-dimensional Dirac nodal loop magnons in collinear antiferromagnets

Abstract

We study the nontrivial linear magnon band crossings in the collinear antiferromagnets on the two-dimensional (2D) CaVO lattice, also realized in some iron-based superconductors such as AFe${}_{1.6+x}$Se${}_2$ (A = K, Rb, Cs). It is shown that the combination of space-inversion and time-reversal symmetry ($\mathcal{P}\mathcal{T}$-symmetry) leads to doubly-degenerate eight magnon branches, which cross each other linearly along a one-dimensional loop in the 2D Brillouin zone. We show that the Dirac nodal loops (DNLs) are not present in the collinear ferromagnet on this lattice. Thus, the current 2D antiferromagnetic DNLs are symmetry-protected and they provide a novel platform to search for their analogs in 2D electronic antiferromagnetic systems.

arXiv comment4 pages, 3 figures. To appear as a Letter in J. Phys. Cond. Mat

References in corpus (29)

• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• Topological Insulators with Inversion Symmetry
• Discovery of a Weyl Fermion Semimetal and Topological Fermi Arcs
• Antiferromagnetic spintronics
• Antiferromagnetic spintronics
• Dirac semimetal and topological phase transitions in A3Bi (A=Na, K, Rb)
• Dirac semimetal in three dimensions
• Experimental discovery of Weyl semimetal TaAs
• Topological nodal semimetals
• Topological nodal line semimetals with and without spin-orbital coupling
• Antiferromagnetic order and spin dynamics in iron-based superconductors
• Nodal-chain metals
• Dirac Fermions in Antiferromagnetic Semimetal
• Topological nodal-line semimetals in alkaline-earth stannides, germanides and silicides
• Weyl magnons in breathing pyrochlore antiferromagnets
• Tunable magnon Weyl points in ferromagnetic pyrochlores
• Dirac magnons in honeycomb ferromagnets
• Quantum magnetism in two dimensions: From semi-classical Néel order to magnetic disorder
• Dirac and nodal line magnons in three-dimensional antiferromagnets
• Plaquette Resonating-Valence-Bond Ground State of CaV${}_4$O${}_9$
• Two-Dimensional Node-Line Semimetals in a Honeycomb-Kagome Lattice
• Spin Waves and magnetic exchange interactions in insulating Rb${}_{0.89}$Fe${}_{1.58}$Se${}_2$
• Magnon nodal-line semimetals and drumhead surface states in anisotropic pyrochlore ferromagnets
• Two-dimensional topological nodal line semimetal in layered $X_{2}Y$ ($X$ = Ca, Sr, and Ba; $Y$ = As, Sb, and Bi)
• Weyl magnons in noncoplanar stacked kagome antiferromagnets
• Antiferromagnetic Topological Nodal Line Semimetals
• Dirac Magnon Nodal Loops in Quasi-2D Quantum Magnets
• The Heisenberg model on the 1/5-depleted square lattice and the CaV4O9 compound
• Magnonic triply-degenerate nodal points

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• Competing orders in a frustrated Heisenberg model on the Fisher lattice