Dirac semimetal phase in hexagonal LiZnBi

Based on first-principles calculations, we find that LiZnBi, a metallic hexagonal ABC compound, has a pair of three-dimensional Dirac nodes and exhibits nontrivial topological properties under proper strain configurations. The nontrivial topological nature of the strained LiZnBi is directly demonstrated by calculating its Z2 index and the surface states. The low-energy states are shown to be sensitive to strain configurations, and we propose that these nontrivial topological properties can be observed under compressive in-plane strain in experiments. The finding of the Dirac semimetal phase in LiZnBi may intrigue further research on the topological properties of hexagonal ABC materials and promote new practical applications.