Controlled transport through a single molecule.

ROM 2013-1
Author: A. Kumar, R. Heimbuch, B. Poelsema, H. J. W. Zandvliet
Institute: Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
Publication: [1] A. Kumar, R. Heimbuch, B. Poelsema, and H. J. W. Zandvliet, Journal of Physics: Condensed Matter 24, 082201 (2012). [2] R. Heimbuch, H. Wu, A. Kumar, B. Poelsema, P. Schön, G. J. Vancso, and H. J. W. Zandvliet, Phys. Rev. B 86, 075456 (2012).
Instrument: LT STM

We demonstrate how an electrode–molecule–electrode junction can be controllably opened and closed by careful tuning of the contacts’ interspace and voltage. The molecule, an octanethiol, flips to bridge a ~1 nm interspace between substrate and scanning tunneling microscope tip when an electric field exceeds a threshold (switch ‘on’). Reducing the field below this threshold value leads to the reproducible detachment of the octanethiol (switch ‘off’). Once contacted, a further reduction of the contacts’ interspace leads to an increase of the conductance of the molecule.

Name and email of corresponding author:
[1] A. Kumar,
[2] R. Heimbuch,