Magnetic semimetals host massless quasiparticles

Mechanical topological semimetals with massless quasiparticles and a finite Berry curvature

A topological quantum phase requires a finite momentum-space Berry curvature which, conventionally, can arise through breaking the inversion or the time-reversal symmetry so as to generate nontrivial, topologically invariant quantities associated with the underlying energy band structure (e.g., a finite Chern number). For conventional graphene or graphenelike two-dimensional (2D) systems with g...

Massless Majorana-Like Charged Carriers in Two-Dimensional Semimetals

The band structure of strongly correlated two-dimensional (2D) semimetal systems is found to be significantly affected by the spin-orbit coupling (SOC), resulting in SOC-induced Fermi surfaces. Dirac, Weyl and Majorana representations are used for the description of different semimetals, though the band structures of all these systems are very similar. We develop a theoretical approach to the b...

Topological Quasiparticles: Magnetic Skyrmions

Magnetic skyrmions are topologically distinct spin textures and can be stable with quasi-particle like behavior, such that they can be manipulated with very low electric currents. This makes them interesting for extreme low-power information technologies [1], where data is envisioned to be encoded in topological charges, instead of electronic charges as in conventional semiconducting devices. U...

Distinct Evolutions of Weyl Fermion Quasiparticles and Fermi Arcs with Bulk Band Topology in Weyl Semimetals.

The Weyl semimetal phase is a recently discovered topological quantum state of matter characterized by the presence of topologically protected degeneracies near the Fermi level. These degeneracies are the source of exotic phenomena, including the realization of chiral Weyl fermions as quasiparticles in the bulk and the formation of Fermi arc states on the surfaces. Here, we demonstrate that the...

Electric Charge Localized on Magnetic Domain Walls in Weyl Semimetals