2016/12/31 by Motohiko Ezawa · 35 citations
Materials Science · Physics and Astronomy · #Anomaly (physics) #Band gap #Chiral anomaly #Condensed matter physics #Electronic band structure #Fermion #Graphene research and applications #Landau quantization #Law #Magnetic field #Physics #Quantum Mechanics and Non-Hermitian Physics #Quantum mechanics #Representation (politics) #Semimetal #Theoretical physics #Topological Materials and Phenomena #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.95.205201
published in Physical review. B./Physical review. B 95(20) (American Physical Society) · 9 pages, 10 figures
arxiv created 2017/03/08 · openalex publication_date 2017/05/03 · arxiv updated 2017/05/05 · openalex created_date 2019/08/13 · openalex updated_date 2026/08/05
Multiband touchings together with the emergence of fermions exhibiting linear dispersions have recently been predicted and realized in various materials. We first investigate the Adler-Bell-Jackiw chiral anomaly in these multiband touching semimetals when they are described by the pseudospin operator in high-dimensional representation. By evaluating the Chern number, we show that the anomalous Hall effect is enhanced depending on the magnitude of the pseudospin. It is also confirmed by the analysis of the Landau levels when magnetic field is applied. Namely, charge pumping occurs from one multiband touching point to another through multichannel Landau levels in the presence of parallel electric and magnetic fields. We also show a pair annihilation of two multiband touching points by photoirradiation. Furthermore, we propose generalizations of Dirac semimetals, multiple Weyl semimetals, and loop-nodal semimetals to those composed of fermions carrying pseudospins in high-dimensional representation. Finally we investigate the three-band touching protected by the C3 symmetry. We show that the three-band touching point is broken into two Weyl points by photoirradiation.