Local control of the conductivity of single atoms and molecules probed by scanning tunneling microscopy and spectroscopy

• Applicant: Professor Dr. Peter Wahl
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2006 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 25126281

Electronic transport through a single molecule bonded to a metallic substrate will be studied by local probe spectroscopy at low temperatures (0.5-6K). We want to complement morphology and electronic structure of the molecules obtained by conventional scanning tunneling microscopy/spectroscopy by transport properties extracted from point contact spectroscopy. This combination not only offers a unique opportunity to deepen our understanding of the role of the electronic and vibrational excitations in molecular electronic transport, and to address the determining role of the molecule-metal contacts. Functional molecules with structural and/or electronic/magnetic bistability will be attached to copper single crystal surfaces via carboxylate bonding. The influence of the geometric and chemical structure on the molecule-metal contact will be studied in detail and we aim to control the transport through manipulation of the local contact environment. For the functional molecules incorporating magnetic centers we will also explore the possibility to modulate the transport with magnetic field via the Kondo screening.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1243: Quantum Transport at the Molecular Scale
• Participating Person: Professor Dr. Klaus Kern