A kiwi from the atom lab to brighten your day. All kiwis are made from atoms – the only difference is that the one on the right was made today from rubidium atoms.

The image is made with 20000 atoms expanding from a Bose-Einstein Condensate of rubidium atoms in a plane (the plane is made by interfering two 1064 nm laser beams, having a lower frequency that the main resonance in rubidium).

The image on the left is this is made with the spatial light modulator, which lets us make any image that we like. 532 nm light has a higher frequency than the main resonance, and is hence repulsive for rubidium, so by making the outline of the shape with 532 nm light, the atoms expand until they “hit the wall”, which in this case is in the shape of a kiwi.
Some parameters:
  • The kiwi is 150 micrometres in length.
  • The atoms have a temperature of 10 nK.
  • The height of the barrier made by the green laser is 2 microkelvin.