The Asin of a Jean

In medieval Europe, there were artifacts often cemented into the wall in the town square. The idea of having an artifact was extremely widespread throughout the world. At the time of the French Revolution, it was said that there were something like 100,000 different measurements across Europe. So what did they do? They chose the earth as the standard of length.

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NIST Fellow William D. Phillips received the 1997 Nobel Prize in Physics “for development of methods to cool and trap atoms with laser light.” He shared the honor with Steven Chu and Claude Cohen-Tannoudji. Their work combined to create some of the most important technologies of modern atomic physics, which thousands of researchers worldwide employ today for a wide variety of applications. Today, he joins us to discuss time keeping throughout history and breakthroughs on the way to the best clocks ever made!

Phillips began his experiments with laser trapping and cooling shortly after he arrived in 1978 at the National Bureau of Standards (the agency that became NIST), with the intent of creating a more accurate atomic clock. Several of his innovations in the following years became landmarks in the field. These included a device using a laser along with a magnetic field to decelerate and cool an atomic beam (the “Zeeman slower”); demonstrating the first device that trapped electrically neutral atoms (a magnetic trap); and measuring a temperature far below that predicted by the accepted theory of laser cooling at the time (known as sub-Doppler cooling).