Momentum-space structure of surface states in a topological semimetal with a nexus point of Dirac lines
Hyart, T., & Heikkilä, T. (2016). Momentum-space structure of surface states in a topological semimetal with a nexus point of Dirac lines. Physical Review B, 93(23), Article 235147. https://doi.org/10.1103/PhysRevB.93.235147
Published inPhysical Review B
© 2016 American Physical Society. Published in this repository with the kind permission of the publisher.
Three-dimensional topological semimetals come in different variants, either containing Weyl points or Dirac lines. Here we describe a more complicated momentum-space topological defect where several separate Dirac lines connect with each other, forming a momentum-space equivalent of the real-space nexus considered before for helium-3. Close to the nexus the Dirac lines exhibit a transition from type I to type II lines. We consider a general model of stacked honeycomb lattices with the symmetry of Bernal (AB) stacked graphite and show that the structural mirror symmetries in such systems protect the presence of the Dirac lines, and also naturally lead to the formation of the nexus. By the bulk-boundary correspondence of topological media, the presence of Dirac lines lead to the formation of drumhead surface states at the side surfaces of the system. We calculate the surface state spectrum, and especially illustrate the effect of the nexus on these states.
PublisherAmerican Physical Society
Publication in research information system
MetadataShow full item record
Related funder(s)Academy of Finland
Funding program(s)Centre of Excellence, AoF
Additional information about fundingThis work was supported by the Academy of Finland Centre of Excellence program (Project No. 284594) and the European Research Council (Grant No. 240362-Heattronics).
Showing items with similar title or keywords.
Large enhancement of spin pumping due to the surface bound states in normal metal–superconductor structures Silaev, Mikhail (American Physical Society (APS), 2020)We show that the spin pumping from ferromagnetic insulator into the adjacent metallic spin sink can be strongly stimulated by the superconducting correlations. The key physical mechanism responsible for this effect is the ...
Collective amplitude mode fluctuations in a flat band superconductor formed at a semimetal surface Kauppila, Ville J.; Hyart, Timo; Heikkilä, Tero (American Physical Society, 2016)We study the fluctuations of the amplitude (i.e. the Higgs-Anderson) mode in a superconducting system of coupled Dirac particles proposed as a model for possible surface or interface superconductivity in rhombohedral ...
Löytäinen, Topi (2016)Työssä tarkastellaan kvanttiteorian ominaisarvo-ongelman matemaattisia perusteita asettamalla vaatimuksia Hilbertin avaruudelle. Työ seuraa läheisesti John von Neumannin käsittelyä kirjassa ’’Mathematical Foundations of ...
ALICE Collaboration (American Physical Society, 2020)The first evidence of spin alignment of vector mesons (K*0 and ϕ) in heavy-ion collisions at the Large Hadron Collider (LHC) is reported. The spin density matrix element ρ00 is measured at midrapidity (|y|<0.5) in Pb-Pb ...
Moisala, Terhi (2015)Tutustun Pro Gradu -työssäni topologisiin materiaaleihin ja perehdyn grafeenin sekä romboedrisen grafiitin ominaisuuksiin tästä näkökulmasta. Erityisesti tutkin grafeenin alihilasymmetrian rikkoutumisen vaikutuksia grafiitissa ...