Modelling single molecule circuits

DIPC Seminars

Héctor Vázquez, Institute of Physics, Academy of Sciences of the Czech Republic
Donostia International Physics Center (DIPC).Paseo Manuel de Lardizabal, 4, Donostia
Add to calendar
Subscribe to Newsletter
Modelling single molecule circuits In this talk I will describe my recent work on single molecule transport modelling. I will first address the role of metal-molecule chemical linkers and will focus on highly-conducting Au-C links. These covalent Au-C bonds between the electrodes and the molecular backbone result in conductance that is much higher than with other linkers [1] and result in near-resonant transport [2]. Theory reveals the good electronic coupling in Au–C links, which have near ideal contact resistance. I will also address quantum interference effects in single molecule transport. I will describe the flow of current through molecules that have two backbones bonded in parallel to the electrodes. The calculated and measured conductance of these double-backbone molecules can be more than twice (e.g. ~3×) that of their single-backbone counterparts due to constructive quantum interference [3]. References: [1] Z-L Cheng, R. Skouta, H. Vázquez, J. Widawsky, S. Schneebeli, M.S. Hybertsen, R.Breslow and L.Venkataraman, 'In situ formation of highly conducting covalent Au-C contacts for single-molecule junctions', Nature Nanotechnology 6 353 (2011). [2] W. Chen, J.R. Widawsky, H. Vázquez, S. Schneebeli, M.S. Hybertsen, R. Breslow and L. Venkataraman, 'Highly Conducting pi-Conjugated Molecular Junctions Covalently Bonded to Gold Electrodes', J. Am. Chem. Soc. 133 17160 (2011). [3] H. Vázquez, R. Skouta, S. Schneebeli, M. Kamenetska, R.Breslow, L. Venkataraman and M.S. Hybertsen, 'Probing the Conductance Superposition Law in Single Molecule Circuits with Parallel Paths', Nature Nanotechnology 7 663 (2012).