Abstract: The very accurate quantization of charge transport or electron current is achieved within a heterostructure substrate by defining a quantum wire within the substrate and propagating a a.c. potential characterized by a travelling wave envelope along the length of the quantum wire. The travelling wave a.c. potential is applied to the length of the quantum wire by two opposing lateral gate arrays defined within the substrate. For each gate on the array is provided a corresponding gate on the opposing array which is offset in the direction of the current transport by a predetermined distance. A succeeding space is then provided in both arrays where there is no gate. An offset a.c. potential is then applied to the gate of one array, the offset gate of the opposing array and to the array as a whole through an overlying gate running the longitudinal length of the quantum, wire which gate applies a spatially independent a.c. potential along the length of the quantum wire.