Gate-Tunable Quantum Dot in a High Quality Single Layer MoS${}_2$ Van der Waals Heterostructure

Abstract

We have fabricated an encapsulated monolayer MoS${}_2$ device with metallic ohmic contacts through a pre-patterned hBN layer. In the bulk, we observe an electron mobility as high as 3000 cm${}^2$/Vs at a density of 7 $\times$ 10${}^{12}$ cm${}^{-2}$ at a temperature of 1.7 K. Shubnikov-de Haas oscillations start at magnetic fields as low as 3.3 T. By realizing a single quantum dot gate structure on top of the hBN we are able to confine electrons in MoS${}_2$ and observe the Coulomb blockade effect. By tuning the middle gate voltage we reach a double dot regime where we observe the standard honeycomb pattern in the charge stability diagram.