Number 400 (Story #2), October 30, 1998 by Phillip F. Schewe and Ben Stein|
THE CONDUCTANCE OF A SINGLE MOLECULE has been measured directly by having the molecule bridge the break in a thin wire. Scientists at Yale use the wire ends as electrodes for sending current through a small polymer molecule poised between them. Previously the electrical properties of single molecules had been studied, but this was through the use of a probe microscope which samples the molecule across a vacuum gap. Mark Reed (203-432- 4300, email@example.com) reports that the current-versus-voltage characteristics of the molecule (important for any potential device application) resemble those of a quantum dot in that certain electron energies are preferred over others, in this case because of the internal energy levels of the molecule itself. See figure at Physics News Graphics. (Paper to be presented at the American Vacuum Society (AVS) meeting in Baltimore, 2-6 November 1998.