Direct determination of the energy required to operate a single molecule switch.
Using a noncontact atomic-force and scanning-tunneling microscope in ultrahigh vacuum, we have measured the switching energy of a single molecule switch based on the rotation of a di-butyl-phenyl leg in a Cu-tetra-3,5 di-tertiary-butyl-phenyl porphyrin. The mechanics and intramolecular conformation of the switched leg is controlled by the tip apex of the noncontact atomic-force microscope. The comparison between experimental and calculated force curves shows that the rotation of the leg requires an energy less than 100 x 10(-21) J, which is 4 orders of magnitude lower than state-of-the-art transistors.
Loppacher
Ch
Ch
Institute of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland. Loppacher@iapp.de
Guggisberg
M
M
Pfeiffer
O
O
Meyer
E
E
Bammerlin
M
M
Lüthi
R
R
Schlittler
R
R
Gimzewski
J K
JK
Tang
H
H
Joachim
C
C