Non-Abelian properties of electron wave packets in Dirac semimetals A${}_3$Bi (A=Na,K,Rb)

Abstract

The motion of electron wave packets in the Dirac semimetals A${}_3$Bi (A=Na,K,Rb) is studied in a semiclassical approximation. Because of the two-fold degeneracy of the Dirac points and a momentum-dependent gap term in the low-energy Hamiltonian, the associated Berry curvature is non-Abelian. In the presence of background electromagnetic fields, such a Berry curvature leads to a splitting of trajectories for the wave packets that originate from different Dirac points and chiral sectors. The nature of the splitting strongly depends on the background fields as well as the initial chiral composition of the wave packets. In parallel electric and magnetic fields, while a well pronounced valley splitting is achieved for any chirality composition, the chirality separation takes place predominantly for the initially polarized states. On the other hand, in perpendicular electric and magnetic fields, there are clear deviations from the conventional Abelian trajectories, albeit without a well-pronounced valley splitting.

15 pages, 9 multi-panel figures; published version

References in corpus (9)

• Weyl and Dirac Semimetals in Three Dimensional Solids
• Classification of stable three-dimensional Dirac semimetals with nontrivial topology
• Berry Curvature, Triangle Anomalies, and the Chiral Magnetic Effect in Fermi Liquids
• Discovery of Weyl fermion semimetals and topological Fermi arc states
• Lorentz Invariance in Chiral Kinetic Theory
• Electron scattering in tantalum monoarsenide
• Chiral transport equation from the quantum Dirac Hamiltonian and the on-shell effective field theory
• Dirac semimetals $A_{3}Bi$ ($A$=Na,K,Rb) as $Z_2$ Weyl semimetals
• Surface Fermi arcs in $Z_2$ Weyl semimetals $A_{3}Bi$ (A=Na, K, Rb)

Cited by in corpus (6)

• Semiclassical equations of motion for disordered conductors: extrinsic interband velocity, corrected collision integral and spin-orbit torques
• Influence of interactions on the anomalous quantum Hall effect
• Fermi arcs and DC transport in nanowires of Dirac and Weyl semimetals
• A Note on Bloch theorem
• Theory of wavepacket transport under narrow gaps and spatial textures: non-adiabaticity and semiclassicality
• Revealing the non-adiabatic and non-Abelian multiple-band effects via anisotropic valley Hall conduction in bilayer graphene