Exploring - and -decay-induced quenching of the Th nuclear-clock isomer in solid-state hosts
Y. Elskens🇧🇪 · M. Athanasakis-Kaklamanakis🇨🇭 · S. Arasada Pradeep🇩🇪 · M. Au🇨🇭 · S. Bara🇧🇪 · M. Bartokos🇦🇹 · K. Beeks🇦🇹 · C. Bernerd🇨🇭 · B. Biesmans🇧🇪 · S. Casci🇧🇪 · P. Chhetri🇩🇪 · K. Chrysalidis🇨🇭 and 43 other authors
The radiative decay dynamics of an ensemble of Th nuclei embedded in CaF and MgF is investigated. The isomer is populated through decay of Ac following ion implantation, and its radiative decay is detected using vacuum-ultraviolet spectroscopy and measured as a function of time. This allows to identify and quantify the quenching of the radiative-decay signal induced by or radiation. The quenching probability density is determined in different CaF crystals and in a MgF crystal, revealing differences up to two orders of magnitude between the investigated samples and a strong dependence on the host material and defect densities. The results support a microscopic mechanism mediated by charge carriers in which electronic excitations created by the decay radiation are captured near Th defects, thereby favoring non-radiative decay channels.