Our "NanoTube" collection of informative and noteworthy videos
in the areas of nanosciences and nanotechnology The world's
smallest smiley This atomic smiley is written on a Ag(111)
surface by manipulating individual silver atoms extracted from
the native surface with the STM-tip. It has a radius of 18 nm.
It is probably the world smallest smiley. It is created for
public outreach, especially for the kids to inspire nanoscience.
The big smile of this smiley is generated by surface electron
standing waves. Yes, at the nanoscale, the electron can behave
not only as a particle but also as a wave, a famous phenomenon
known as wave particle duality. That is why we can see the
electrons as water waves here creating a big smile.