“…Subsequently, the ions are implanted into a SiO 2 surface, which is expected to provide a sufficiently large band-gap to suppress the isomer's internal conversion decay channel. Thorium-oxide coatings on a SiO 2 surface were investigated as a substrate for observing the isomer's radiative decay and for the development of a solid-state nuclear clock in [32,33,35,40,381,384,385]. In 2018, laserplasma excitation of the isomeric state was reported, together with a determination of the isomer's excitation energy to 7.1 ± 0.1 eV and a value for the isomer's radiative half-life of 1880 ± 170 s [43] (see also [44,203]).…”