The image of the free-falling trapped atoms at 10-5K, where different colors corespond to different atomic density. The signal above is the image taken at t = 0.01s, while the one below is at 0.03s. The actual scale of image is calibrated by the displacement of the free falling atoms within a given time, and the expansion of the atoms is measured to estimate its temperature.
In this movie, trapped atoms follow the zero of the quadrupole magnetic field which is affected by a magnet outside the trapping cell.
