Non-linear contribution to intensity-voltage characteristics of gold nanowires

In this paper, we present experimental results for room temperature (I-V) c haracteristics of gold nanowires whose zero current conductance is quantize d. We have analysed more throroughly the (I-V) characteristics of high stab ility nanoscopic gold contacts changing several parameters such as the form ation technique (MCBJ, nanolithography, STM related Technique) or the envir onment conditions around the nanowire (vacuum, air, polymer, non-conductive substrate). In all these experiments, a faster than linear increase of the current was observed, but at different threshold voltages depending on the situation: 0.1V for "free standing" nanowires (in air or vacuum), 0.2 to 0 .5V for non "free standing", i.e., nanowires deposited on a substrate or em bedded in a polymer. (C) 1999 Acta Metallurgica Inc.