Single-charge tunnelling in n- and p-type strained silicon germanium on silicon-on-insulator

Dual-gate quantum dot transistors have been fabricated in n- and p-type str ained SiGe on silicon-on-insulator. In single-gate modes, the narrow and wi de gates on opposing sides modulate the single-charge tunnelling events in the quantum dot. When both gates are coupled together, the resultant modula tion implies that capacitive coupling via the substrate controls the tunnel ling. The coupling causes constructive-destructive effects in lifting-resto ring the Coulomb blockade condition in the SiGe quantum dots.