Topological Magnon Bands and Unconventional Thermal Hall Effect on the Frustrated Honeycomb and Bilayer Triangular Lattice
arXiv:1705.08892 · doi:10.1088/1361-648X/aa7dd2
Abstract
In the conventional ferromagnetic systems, topological magnon bands and thermal Hall effect are due to the Dzyaloshinskii-Moriya interaction (DMI). In principle, however, the DMI is either negligible or it is not allowed by symmetry in some quantum magnets. Therefore, we expect that topological magnon features will not be present in those systems. In addition, quantum magnets on the triangular-lattice are not expected to possess topological features as the DMI or spin-chirality cancels out due to equal and opposite contributions from adjacent triangles. Here, however, we predict that the isomorphic frustrated honeycomb-lattice and bilayer triangular-lattice antiferromagnetic system will exhibit topological magnon bands and topological thermal Hall effect in the absence of an intrinsic DMI. These unconventional topological magnon features are present as a result of magnetic-field-induced non-coplanar spin configurations with nonzero scalar spin chirality. The relevance of the results to realistic bilayer triangular antiferromagnetic materials are discussed.
7 pages, 8 figures. Final version to be published in J. Phys.: Condens. Mat
References in corpus (15)
- Observation of the Magnon Hall Effect
- Theoretical prediction of rotating magnon wavepacket in ferromagnets
- Topological Magnon Insulator in Insulating Ferromagnet
- Spin chirality on a two-dimensional frustrated lattice
- Hall effect of triplons in a dimerized quantum magnet
- Thermal Hall Effect of Spins in a Paramagnet
- Unconventional Anomalous Hall Effect in the Metallic Triangular-Lattice Magnet PdCrO2
- Topological Thermal Hall Effect in Frustrated Kagomé Antiferromagnets
- Emergence of nontrivial magnetic excitations in a spin liquid state of kagome volborthite
- Disordered Ground State and Magnetic Field-Induced Long-Range Order in an S=3/2 Antiferromagnetic Honeycomb Lattice Compound Bi3Mn4O12(NO3)
- Spin liquids on a honeycomb lattice: Projective Symmetry Group study of Schwinger fermion mean-field theory
- spin liquid and chiral antiferromagnetic phase in Hubbard model on the honeycomb lattice: duality between Schwinger-fermion and Schwinger-boson representations
- Plaquette valence-bond ordering in J_1-J_2 Heisenberg antiferromagnet on the honeycomb lattice
- Field-induced decays in triangular-lattice antiferromagnets
- Chiral spin density wave order on frustrated honeycomb and bilayer triangle lattice Hubbard model at half-filling