David Wineland - Atomic Clocks + Board meeting

For many centuries, and continuing today, a primary application of accurate clocks is for precise navigation.  For example, GPS enables us to determine our distance from the (known) positions of satellites by measuring the time it takes for a pulse of radiation emitted by the satellite to reach us.  The more accurately we can measure this time, the more accurate our position is known. 

Atoms absorb electromagnetic radiation at precise discrete frequencies.  Knowing this, a recipe for making an atomic clock is simple to state: we first need an oscillator to produce the radiation and a device that tells us when the atoms absorb it.  To make a clock from this setup, we then simply count cycles of the oscillator; the duration of a certain number of cycles defines a unit of time, for example, the second.  Today, the most accurate clocks count cycles of radiation corresponding to optical wavelengths, around a million billion per second.  At this level, many interesting effects, including those due to Einstein’s relativity, must be accounted for.

BIO:

David Wineland received a B.A. degree from the University of California, Berkeley in 1965 and a Ph.D. from Harvard University in 1970.  Following a postdoctoral position at the University of Washington in Seattle, he joined the Time and Frequency Division of NIST (National Institute of Standards and Technology) in Boulder, Colorado, from 1975 to 2017, where he was a group leader and NIST Fellow.  He is now a Philip H. Knight Distinguished Research Chair and Research Professor in the Department of Physics at the University of Oregon in Eugene.

Starting with graduate school, a long-term goal of his work has been to increase the precision of atomic spectroscopy, the measurement of the frequencies of atoms’ characteristic vibrations.  This research has applications to making better atomic clocks and has led to experiments that enable precise control of atomic energy levels and atomic motion.  Such control can be applied to metrology whose precision is limited only by the constraints of quantum mechanics and to demonstrations of the basic building blocks of a quantum computer.  For this work, he shared the 2012 Nobel Prize in Physics with Serge Haroche, Collège de France, Paris.