Emergent Weyl-like points in periodically modulated systems and Floquet engineering

Fang Qin, Rui Chen

Published 2024-12-05Version 1

We investigate a three-dimensional topological phase resembling a Weyl semimetal, modulated by a periodic potential and engineered through Floquet dynamics. This system is constructed by stacking two-dimensional Chern insulators and hosts Weyl-like points defined in the parameter space $(k_x, k_y, z)$, distinct from conventional Weyl points in momentum space $(k_x, k_y, k_z)$. The Weyl-semimetal-like phase exhibits characteristics akin to those of Weyl semimetals, including linear dispersion near the Weyl-like points, nontrivial bulk topology, and the presence of Fermi arcs connecting the Weyl-like points. Unlike traditional Weyl semimetals, these features manifest in real space rather than momentum space. Additionally, we compute the layer-resolved Floquet Hall conductivity and demonstrate that the positions of the Weyl-like points can be controlled via high-frequency laser pumping.