Inducing and Manipulating Heteroelectronic States in a Single MoS2 Thin Flake

By dual gating a few-layer MoS2 flake, we induce spatially separated electronic states showing superconductivity and Shubnikov–de Haas (SdH) oscillations. While the highly confined superconductivity forms at the K/K′ valleys of the topmost layer, the SdH oscillations are contributed by the electrons residing in the Q/Q′ valleys of the rest of the bottom layers, which is confirmed by the extracted Landau level degeneracy of 3, electron effective mass of 0.6me, and carrier density of 5×10^12  cm^−2. Mimicking conventional heterostructures, the interaction between the heteroelectronic states can be electrically manipulated, which enables “bipolarlike” superconducting transistor operation. The off-on-off switching pattern can be continuously accessed at low temperatures by a field effect depletion of carriers with a negative back gate bias and the proximity effect between the top superconducting layer and the bottom metallic layers that quenches the superconductivity at a positive back gate bias.