Physical Review Letters

Direct determination of the energy required to operate a single molecule switch


The intramolecular conformation of an individual molecule that can be switched through the forced rotation of a single C-C bond and its mechanics quantitatively determined using noncontact atomic force microscopy (AFM) was shown. As such, an excellent agreement between theory and experiment on both the absolute values and the vertical position of the force minima was found. Comparison between experimental and calculated force curves shows that the rotation of a di-phenyl-butyl leg requires an energy less than 100 zJ, which was 4 orders of magnitude lower than state-of-the-art field effect transistors.