AVS 50th International Symposium
    Organic Films and Devices Wednesday Sessions
       Session OF+NS-WeM

Paper OF+NS-WeM3
Understanding Charge Transport in Molelcular Electronics

Wednesday, November 5, 2003, 9:00 am, Room 318/319

Session: Molecular Electronics
Presenter: J.G. Kushmerick, Naval Research Laboratory
Authors: J.G. Kushmerick, Naval Research Laboratory
R. Shashidhar, Naval Research Laboratory
Correspondent: Click to Email
We use an experimentally simple crossed-wire tunnel junction to interrogate how factors such as metal-molecule coupling, molecular structure and the choice of metal electrode influence the current-voltage characteristics of a molecular junction. Results on junctions with symmetric and asymmetric metal-molecule contacts demonstrate that a specific molecular core can act either as a molecular wire or a molecular rectifier depending on its coupling to the metal electrodes. By tuning the coupling at the two metal-molecule interfaces-through the use of different attachment chemistries and metal electrodes-we are able to control the extent of current rectification. Experimental measurements and theoretical calculations demonstrate that the conductance of a molecular wire can be directly related to how well it's @pi@-conjugated backbone mimics an ideal one-dimensional metal. Finally, we will show that the conductance of a molecular junction scales with the number of molecules contacted, and that the @pi@-systems of molecular wires connected in parallel are not strongly coupled. Initial results demonstrating the utility of in situ vibrational spectroscopy to characterize the molecular junction will also be presented.