One-dimensional states in transition metal dichalcogenide interfaces: an analytical and computational approach

The growth and exfoliation of 2D materials have led to the creation of edges and novel interfacial states (IFS) at the juncture between different crystals. IFS can exist between different materials, such as at a lateral interface of MoS₂/MoSe₂, or between different crystalline phases of the same material. IFS inherit properties from both crystals, giving rise to robust states with unique non-parabolic dispersion and strong spin-orbit effects. Although several computational approaches have been used to describe IFS in different materials, it is important to have analytical insights into the nature of such states. We present here a general theory of lateral IFS for Dirac-like HHamiltonians with different characteristics across the interface. We focus here on results for IFS in MoS₂/WS₂, and study their behavior for different interfaces (zigzag and armchair). We also compare these findings to numerical results obtained from a suitable 3-orbital tight-binding model of the structure, which considers experimental and DFT parameters as input. We finally propose different scenarios where IFS could act as effective 1D-physics hosts.