Chiral Gold Nanotube
Kunio Takayanagi
Tokyo Institute of Technology, Physics Department,
2-12-1 Oh-okayama, Meguro, Tokyo, 152-8551 Japan
One-dimensional matter is often has helical structures like DNA and carbon nanotubes.
We fabricated metal nanowires by using a new technique that combines ultra-high-vacuum transmission electron microscope and scanning tunneling microscope. We report helical structure of the gold (and platinum) nanowire that consists of coaxial nanotubes, each of which has n-membered atomic strands coiling around the axis of the nanowire. The gold helical nanowire has geometry similar to the carbon nanotube, the honeycomb network of the graphite sheet being replaced to the triangular network. We discuss about they structure having the magic number seven, their helical nature, and their electronic conductance quantized in the unit of 2e2/h. Questions on stability and conductance of helical metal tubes other than gold and platinum will be discussed.