Several Nobel prizes in physics are related to the development of the techniques to manipulate quantum properties of individual atoms (e.g. 1989, 1996, 1997, 2001, 2005, 2012, 2018).
Evidence for radiation pressure, force due to light on atoms, was demonstrated independently by Lebedev, and Nichols and Hull in 1901.
One of the major technical challenges in Doppler cooling was increasing the amount of time an atom can interact with the laser light.
A Zeeman Slower uses a spatially varying magnetic field to maintain the relative energy spacing of the atomic transitions involved in Doppler cooling.
The development of the first magneto-optical trap (MOT) by Raab et al. in 1987 was an important step towards the creation of samples of ultracold atoms.
The 1997 Nobel prize[6] in physics was awarded for development of methods to cool and trap atoms with laser light and was shared by Steven Chu, Claude Cohen-Tannoudji and William D. Phillips.
The lowest-energy fine structure transitions in alkali atoms enable fluorescence imaging, while a combination of hyperfine and Zeeman sublevels can be used for implementing sub-Doppler cooling.
Ultracold atoms have a variety of applications owing to their unique quantum properties and the great experimental control available in such systems.
Since these tools may differ greatly from those available in the actual condensed matter system, one can thus experimentally probe otherwise inaccessible quantities.