Quantum Materials - 12

Abstract

Quantum confinement and manipulation of degrees of freedom, such as spin and valley, are critical to developing devices suitable for quantum technologies. Two-dimensional (2D) transition metal dichalcogenides (TMDs) are an emerging platform for quantum device development due to the ability to electrically and optically resolve their quantum states, which are indexed by the degrees of freedom. Semiconducting TMDs, especially in the 2H form, possess a direct band gap at the K/K' points in the Brillouin zone, potentially realizing spin-valley qubits with long coherence times due to the spin-valley locking caused by the strong spin-orbit interaction [1][2].
In our study, to realize a TMD-based platform for quantum technology, we have focused on 2D TMDs with nanoscale zero-dimensional confinement potential. For example, monolayer and bilayer lateral heterostructures composed of different TMDs can have confinement potential according to their nanostructure; the core and the intersection can act as confinement sites (Fig. 1). To create these lateral heterostructures with nanoscale potential, we used the metal-organic chemical vapor deposition (MOCVD) method.
Figure.2 shows a height image of a bilayer structure. The bottom triangle has a ribbon-like contrast inside, consistent with the MoS2/WS2 lateral heterostructure. Top triangles also have ribbon-like contrasts, which form zero-dimensional (0D) crossing points.