Imaging electromigration during the formation of break junctions.

Using a scanning electron microscope, we make real-time movies of gold nanowires during the process of electromigration. We confirm the importance of using a small series resistance when employing electromigration to make controlled nanometer-scale gaps suitable for molecular-electronics studies. We are also able to estimate the effective temperature experienced by molecular adsorbates on the nanowire during the electromigration process.