Transport evidence for Fermi-arc mediated chirality transfer in the Dirac semimetal Cd$_3$As$_2$

Understand

Dirac semi-metals show a linear electronic dispersion in three dimension described by two copies of the Weyl equation, a theoretical description of massless relativistic fermions.

• At the surface of a crystal, the breakdown of fermion chirality is expected to produce topological surface states without any counterparts in high-energy physics nor conventional condensed matter systems, the so-called "Fermi Arcs".
• Here we present Shubnikov-de Haas oscillations involving the Fermi Arc states in Focused Ion Beam prepared microstructures of Cd$_3$As$_2$.
• Their unusual magnetic field periodicity and dependence on sample thickness can be well explained by recent theoretical work predicting novel quantum paths weaving the Fermi Arcs together with chiral bulk states, forming "Weyl orbits".