title: Direct determination of the energy required to operate a single molecule switch.
abstract: 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.
authors.affiliation: Institute of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland. Loppacher@iapp.de
authors.forename: Ch
authors.initials: Ch
authors.lastname: Loppacher
authors.forename: M
authors.initials: M
authors.lastname: Guggisberg
authors.forename: O
authors.initials: O
authors.lastname: Pfeiffer
authors.forename: E
authors.initials: E
authors.lastname: Meyer
authors.forename: M
authors.initials: M
authors.lastname: Bammerlin
authors.forename: R
authors.initials: R
authors.lastname: Lüthi
authors.forename: R
authors.initials: R
authors.lastname: Schlittler
authors.forename: J K
authors.initials: JK
authors.lastname: Gimzewski
authors.forename: H
authors.initials: H
authors.lastname: Tang
authors.forename: C
authors.initials: C
authors.lastname: Joachim