Time-reversal invariant realization of the Weyl semimetal phase

摘要: We propose a realization of the Weyl semimetal phase that is invariant under time reversal and occurs due to broken inversion symmetry. consider both simple superlattice model more realistic tight-binding describing an experimentally reasonable HgTe/CdTe multilayer structure. The two models have same underlying symmetry, therefore their low-energy features are equivalent. find between normal insulator topological phases exists for finite range system parameters exhibits number points with robust band touching at Fermi level. This characterized by strong conductivity anisotropy surface states. principal conductivities change in complementary fashion as varied, states only exist region momentum space determined positions points.