Herbert Walther

He has made many contributions to molecular, atomic, and laser spectroscopy. His work on the one-atom masers has allowed fundamental tests of quantum electrodynamic theory for a two-level atom interacting with a single mode of the electromagnetic field. His work on ion trap physics has led to the observation of the condensation of a few atoms into a crystal and has resulted in a nonlinear dynamical model for the Coulomb interaction between the ions. His earlier work deals with the development of stable narrowband lasers and atmospheric monitoring by laser light. With the laser-driven tunneling microscope he has developed a new tool for surface diagnostics.