Rotational Action Spectroscopy in Ion Traps
Rotational action spectroscopy is an experimental method in which rotational spectra of molecules are recorded by action spectroscopy. Action spectroscopy means that the spectrum is recorded not by detecting the absorption of light by the molecules, but by the action of the light on the molecules, e.g., photon-induced destruction of a chemical bond, a photon-triggered reaction, or photodetachment of an electron. Typically, such experiments are performed on molecular ions, which can be well controlled and mass-selected by established guiding and storage techniques. Though coming with many advantages, the application of action schemes to rotational spectroscopy was hampered for a long time by the small energy content of a corresponding photon. Therefore, the first rotational action spectroscopic methods emerged only about one decade ago. Today, there exists a toolbox full of different rotational action spectroscopic schemes. This talk summarizes the different rotational action spectroscopic approaches and gives an outlook on the application of these schemes to exotic hydrogen-helium complexes of the form HnHem+.