June 2019
Intermediate to advanced
512 pages
33h 24m
English
Piet O. Schmidt1,2
1 Physikalisch‐Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
2 Leibniz Universität Hannover, Welfengarten 1, 30167 Hannover, Germany
Laser spectroscopy (LS) has a long history and many applications in fundamental and applied science. Determining the transition frequency between electronic states in isolated atoms using LS represents the most accurate measurement of a natural constant we can currently perform. Today, these measurements approach 18 significant digits in optical clocks and can no longer be stated in hertz, since the unit hertz (based on a hyperfine transition in atomic cesium) can only be realized with an uncertainty ...