Weyl semimetal from the honeycomb array of topological insulator nanowires

Abstract

We introduce a topological semimetal phase with four isolated Weyl nodes in momentum space from a honeycomb arrangement of topological insulator nanowires. This realizes a Weyl semimetal phase in which the topological charge response is absent due to the opposite separation of two pairs of Weyl nodes in the Brillouin zone (BZ). The topological nature of the system manifests itself in the nonzero transverse “valley” current which is proportional to the length of the Weyl nodes' separation vector. In the end, we show that anomalous Hall current can also emerge by considering the Haldane term, i.e., the next-nearest-neighbour inter-wire hopping of the electrons in the presence of a modulating magnetic flux.