By cooling and trapping atoms with laser light, scientists can study them in greater detail, use them in experiments and observe quantum phenomena that occur in the ultra-cool realm. Professor William Daniel Phillips is a pioneer of this technique, for which he was awarded the 1997 Nobel Prize in Physics, along with two other scientists, for his contributions in developing it.
Earlier in his career, Professor Phillips had developed a Zeeman slower, a coil with a varying magnetic field along the axis of which atoms could be slowed by an opposing laser beam. After he moved to the National Bureau of Standards (now the National Institute of Standards and Technology, or NIST) in 1978, he created better methods of measuring the temperature of laser-cooled atoms, and discovered that they could be cooled to a temperature six times lower than the theoretical limit.
He also established a way of using lasers to trap atoms so that they group at regular intervals in space, forming what is called an optical lattice where the atom groups are at a distance of one light wavelength from one another. Atoms in an optical lattice can be cooled to lower temperatures, slowing them further and opening up more opportunities for scientists.
Since his groundbreaking work in laser cooling, he has continued to explore new research fields unlocked by the technique. His laboratory at NIST, for example, is assembling a toolbox of ways to manipulate laser-cooled atoms for various purposes, such as using the atoms as bits in quantum computing, and as replacements for electrons in experiments, including to uncover why some materials are superconductive, and how others become superconductors.
Professor Phillips is also a Distinguished University Professor and College Park Professor of Physics at the University of Maryland, a fellow of the American Physical Society, a fellow and honorary member of the Optical Society of America and a member of the National Academy of Sciences. Apart from the Nobel Prize, he has been conferred the Presidential Rank Award, Service to America Award, Golden Plate Award, Richtmyer Memorial Award and many others.