Seminars Archive

Towards the time-resolved spectroscopy of the photo-induced electron dynamics in nuclear transitions

Abstract
The isomeric transition in Thorium-229 (229mTh) is unique among nuclear transitions due to its exceptionally low excitation energy of ~8.356 eV, placing it in the vacuum ultraviolet (VUV) range. With a radiative lifetime on the order of 10³ seconds, it is a prime candidate for realizing an ultra-precise nuclear clock. Its low transition energy makes it accessible to tabletop laser systems, which have recently enabled the first direct photo-excitation of the isomer. In this seminar, we present our ongoing efforts to establish a platform for investigating photo-induced electron dynamics in nuclear transitions. This includes the compression of sub-nanosecond laser pulses to the few-picosecond regime using a multi-pass cell post-compression scheme, and the generation of VUV radiation via four-wave mixing in a gas-filled hollow-core fiber. Finally, we share preliminary results from an experiment exploring photo-perturbation of the internal conversion decay of 229mTh deposited on the surface of a high-bandgap material.