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“Buckets of BEC with inter-bucket tunnelling”

What? Not Mott?
Pots not dots, lots per pot
…and hot!

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):

O O
O

Atoms moving clockwise (or counter-clockwise) from well to well around the triangle create a vortex.

And that’s exactly what they saw.

Posted by Hamish Johnston on March 7, 2007 5:45 PM | Permalink