Metal-insulator transition in stable one-dimensional arrangements of single gold atoms

The atomic arrangement and conductance during the separation process of gol d point contacts were simultaneously observed in situ by high-resolution tr ansmission electron microscopy. One-dimensional arrangements of gold single atoms, i.e., atomic wires, appeared between two tips at the point contacts . They were stable when their length was increased up to 2.6 nm. The intera tomic distance of the wires was 0.25-0.31 nm. Ir was found that metal-insul ator transition occurs in the wires.