Ultracompact VUV sources

The generation of efficient and tunable vacuum-ultraviolet light (VUV, 100-200 nm, 6-12 eV) is relevant for multiple disciplines. In the field of molecular physics, for example, VUV excitation is optimal for the study of Rydberg state dynamics as well as the temporal evolution of low valence electronic states in a large range of molecular targets. In the field of nuclear physics, instead, VUV laser light may enable the optical excitation of the isomeric transition in Th-229.

To this purpose, we produce compact and portable four-wave-mixing based pump-seed setups for the generation of fs or ps VUV light around 150-nm wavelength in hollow capillaries. We employ Ytterbium-based laser systems for the generation of harmonics over two crystal-based frequency doubling stages and recombine this pump beam with the fundamental seed beam in the hollow capillary, exploiting the advantages of both methods, i.e. nonlinear conversion in crystals and up-conversion in capillaries.

Such VUV light sources are produced within the Photoelement project, that is founded by the Helmholtz young investigator grant VH-NG-1603 led by Andrea Trabattoni.