Since the discovery of fullerenes and carbon nanotubes, the deposits on arc electrodes produced at high gas pressure have been investigated intensely. Despite of the enthusiasm, little work was reported about the initial deposition processes. In principle, such processes could be followed by reducing the amount of products, i.e. a short discharge with a small current. In practice, however, this was prevented by two practical obstacles, arc instability and possible byproducts originated from reactions with remaining impurities in the vacuum chamber. In the present study, we reported a new kind of compact preparation system which allowed stable arc with a small current and a clean environment.

Figure 1 shows a schematic diagram of the system. For higher arc stability, the system had a small cylindrical shape which would reduce the effect of convection. Both electrodes were aligned on the axis inside the cylinder and their gap was adjustable by a micrometer.