Stable $2R$ van der Waals heterostructures of NbS${}_2$ and $M$Se${}_2$ for $M$=Mo and W

Abstract

In this letter, we investigate the stable and commensurate van der Waals heterostructures of metallic and semiconducting $1H$ transition-metal dichalcogenides, NbS${}_2$ and MoSe${}_2$ (WSe${}_2$), which possess almost the same lattice constant of the pristine honeycomb structure. In the most stable structure, the metallic and semiconducting layers are stacked in a similar manner to $3R$ stacking but the period is a pair of a metallic layer and a semiconducting layer. The heterostructure aligns the spin-polarization in each valley among all layers and induces spin-selective charge transfer between the metallic and semiconducting layers. Especially in hetero-trilayers, the electronic spin is conserved due to mirror symmetry along the out-of-plane axis in contrast to the $3R$ stacking structure. A drastic enhancement of spin Hall effect is numerically shown as an example of electronic spin transport phenomena in the hetero-trilayers.

5 pages, 6 figures

References in corpus (7)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Synthesis of Large-Area MoS2 Atomic Layers with Chemical Vapor Deposition
• A Higher-Accuracy van der Waals Density Functional
• k.p theory for two-dimensional transition metal dichalcogenide semiconductors
• First Principles Calculation of Anomalous Hall Conductivity in Ferromagnetic bcc Fe
• Intrinsic spin-valley locking for conducting electrons in metal-semiconductor-metal lateral hetero-structures of $1H$-transition-metal dichalcogenides
• Three-orbital continuous model for $1H$-type metallic transition-metal dichalcogenide monolayers