1. J. Heyrovský
Institute
of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., Dolejškova 3, CZ-18223 Prague
8, Czech Republic
2. Department
of Electrical Engineering
and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
3. Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts
02139, United States
4. National Institute for Materials Science, Namiki 1-1, Tsukuba, Ibaraki
305-0044, Japan