Atomic Clock Keeps Super-Cool Time

Ray LaPierre

Lijun Wang

By measuring the frequencies emitted as atoms transition between energy levels, atomic clocks are among the most advanced devices available for keeping time. In his research, Professor Lijun Wang at Tsinghua University, Beijing, explores how the stringent requirements for these devices can be met using easily transportable apparatus. By combining the latest technological advances in ion trapping, laser cooling, and magnetic shielding, his team has now achieved a design that far exceeds the performance of existing transportable clocks – potentially leading to new capabilities for both high-speed scientific measurements, precision time-keeping, and applications in satellite-based navigation.

Charles S. Adams

Physicists have known for many years that atoms are one of the best measuring devices around – consider, for example, the atomic clock. But it now seems that we are at the start of a new golden age of precision atomic measurements, initiated in part by the development of techniques to cool and manipulate atoms using laser light. As well as providing good time-keeping, atoms make excellent sensors of inertial forces, such as the acceleration due to gravity or the rotation of the Earth.

Kurt Gibble

F Romain