Researchers have developed a clever way to achieve the coldest temperatures ever recorded on Earth. The approach, reported in Nature, may be well-suited to create memory for future quantum computers. Optical lattices are an ideal system in which to attain temperatures ever nearer that limit. The peaks and troughs of intensity in crossed beams of light form a kind of egg-crate arrangement in which atoms are inclined to remain in the troughs - a point of lowest power.
As the atoms are added to each trough or each point in the lattice - it becomes more difficult to add another, in a condition called a blockade. By adjusting how regularly the light beam intensities were distorted, the team was able to remove these "hottest" atoms from the system, leaving only the "coolest" ones last.