Sukhachov P. Dynamical gap generation and surface states in Dirac and Weyl semimetals

The analytical structure of Fermi arcs surface states in effective model of Dirac semimetals A3Bi (A = Na; K; Rb) is studied. It is shown that these materials are Z2 Weyl semimetals. The role of Fermi arc surface states for the new type of quantum oscillations of the density of states is considered. The influence of the interaction effects and magnetic field on their properties is determined. It is shown that the period of quantum oscillations receives the nontrivial dependence on the orientation of the magnetic field. The threshold character of the gap generation in the case of zero magnetic fields in Weyl semimetals is demonstrated. It is shown that in the presence of magnetic field, gap is generated at arbitrary small value of coupling constant.