2017/09/30 by Oğuz Türker, Sergej Moroz · 1 citation
Mathematics · Physics and Astronomy · #Brillouin zone #Cold Atom Physics and Bose-Einstein Condensates #Combinatorics #Geometry #Hamiltonian (control theory) #Homogeneous space #Law #Mathematical physics #Mathematics #NODAL #Physics #Pure mathematics #Quantum many-body systems #Quantum mechanics #Robustness (evolution) #Theoretical physics #Topological Materials and Phenomena #Topology (electrical circuits) #Unitary state #cond-mat.mes-hall #hep-th
paper · pdf · doi:10.1103/physrevb.97.075120
published as Phys. Rev. B 97, 075120 (2018) · 9 pages, 5 figures, published version
openalex publication_date 2018/02/12 · arxiv created 2018/02/28 · arxiv updated 2018/03/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider three-dimensional fermionic band theories that exhibit Weyl nodal surfaces defined as two-band degeneracies that form closed surfaces in the Brillouin zone. We demonstrate that topology ensures robustness of these objects under small perturbations of a Hamiltonian. This topological robustness is illustrated in several four-band models that exhibit nodal surfaces protected by unitary or antiunitary symmetries. Surface states and Nielsen-Ninomiya doubling of nodal surfaces are also investigated.