The transfer of energy between light and matter (from photons to atoms) is not just fascinating and beautiful; it is useful.
The resonant interaction between light and individual atoms in a gas can make those atoms heat up, cool down, or come to a nearly-complete stop in midair. I have been studying laser-cooling of atoms for the past decade, first during my undergraduate work at Bryn Mawr College and later during my graduate and post-doctoral research at Harvard. I continue this research in my experimental work at Middlebury. Our current efforts are focused on assembling the equipment for a laser-cooling system: the lasers themselves, the source of atoms, and the vacuum chamber, optics, and electronics for these experiments. We plan to measure cold atoms that are influenced by external electric fields and also to investigate the forces that affect atoms or ions near solid surfaces.
The first sign of our MOT: 6 August 2014.
The bright cloud of cold rubidium atoms is off-center in the image below. (Size scale: the cloud diameter is probably a few millimeters, at most: next steps include measuring and optimizing.)