Fabrication and Characterization of Metallic Nanowires

The shape of metallic constrictions of nanoscopic dimensions (necks) formed using a scanning tunneling microscope (STM) is shown to depend on the fabrication procedure. Submitting the neck to repeated plastic deformation cycles makes possible to obtain long necks or nanowires. Point-contact spectroscopy results show that these long necks are quite crystalline, indicating that the repeated cycles of plastic deformation act as a "mechanical annealing" of the neck.