What? Not Mott?
Pots not dots, lots per pot
You can only get away with describing your experiment with a poem if you have a Nobel Prize — and JILA’s Eric Cornell has one of them.
The pots are the wells within a two-dimensional optical lattice and they were filled with lots of atoms in the Bose-Einstein condensate state. Atoms can tunnel between wells, so you can also think of this as an array of Josephson junctions (still with me?).
“Buckets of BEC with inter-bucket tunnelling”, is how Cornell described it.
Cornell and his team were looking for a Kosterlitz-Thouless transition in the lattice. This occurs when vortices form in the array above a certain temperature.
The lattice is made up of little triangles that look like this (the “O”s are the wells):
Atoms moving clockwise (or counter-clockwise) from well to well around the triangle create a vortex.
And that’s exactly what they saw.