We report an electrical-field-controlled growth process for the directed bottom-up assembly of one-dimensional palladium nanowires between microfabricated electrodes. The wires, grown from an aqueous palladium salt solution by dielectrophoresis, have a thickness of only 5-10 nm and a length of up to several micrometers. The growth process depends largely on both the strength of the applied ac field and the concentration of the metal salt solution. The conditions for optimum growth are evaluated. Room-temperature current-voltage measurements show ohmic behavior and indicate electromigration effects at higher voltages. Low-temperature transport measurements reveal localization effects with a characteristic resistance minimum at 20 K. The temperature dependence below the minimum shows the wires to be one dimensional in their electron-transport properties. The investigated growth method is capable of building complex circuit patterns for future nanoelectronics.

Dielectrophoresis-assisted growth of metallic nanowires from an aqueous salt solution has been previously reported, but so far there has been no clear understanding of the process leading to such a bottom-up assembly. The present work, based on a series of experiments to grow metallic nano- and microwires by dielectrophoresis, provides a general theoretical description of the growth of such wires from an aqueous salt solution. Palladium nanowires and silver microwires have been grown between gold electrodes from their aqueous salt solution via dielectrophoresis. Silver microwire growth has been observed in situ using light microscopy. From these experiments, a basic model of dielectrophoresis-driven wire growth is developed. This model explains the dependence of the growth on the frequency and the local field enhancement at the electrode asperities. Such a process proves instrumental in the growth of metallic nanowires with controlled morphology and site specificity between the electrodes.

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We investigate the structural, electronic, and transport properties of mechanically deformed Mo6S6 nanowires using a density-functional based tight binding method extended with a Green's functions formalism. We present two interesting results: first, the properties of the wire are not affected by bending, and second, a metal-insulator transition occurs when the wire is twisted. This indicates that molybdenum sulfide nanowires can be used as a nanocable to flexibly transfer information between electromechanical switches, which can be also constructed from the same wires. Hence, our results suggest the Mo6S6 nanowires as unique building blocks for future nanodevices.