Combinatorics

Physics

Geometric phase

Topology (electrical circuits)

Mathematics

Magnetic field

Magnetoresistance

Semimetal

Band gap

Neutrino

Condensed matter physics

Theoretical physics

Dirac sea

Fermion

Dirac (video compression format)

Quantum mechanics

Dirac fermion

Helical Dirac fermion

Annual Review of Materials Research

Three-dimensional (3D) topological semimetals represent a new class of topological matters. The study of this family of materials has been at the frontiers of condensed matter physics, and many breakthroughs have been made. Several topological semimetal phases, including Dirac semimetals (DSMs), Weyl semimetals (WSMs), nodal-line semimetals (NLSMs), and triple-point semimetals, have been theoretically predicted and experimentally demonstrated. The low-energy excitation around the Dirac/Weyl nodal points, nodal line, or triply degenerated nodal point can be viewed as emergent relativistic fermions. Experimental studies have shown that relativistic fermions can result in a rich variety of exotic transport properties, e.g., extremely large magnetoresistance, the chiral anomaly, and the intrinsic anomalous Hall effect. In this review, we first briefly introduce band structural characteristics of each topological semimetal phase, then review the current studies on quantum oscillations and exotic transport properties of various topological semimetals, and finally provide a perspective of this area.

Transport of Topological Semimetals