Overview
- A UCLA, LMU and JGU team reports the first laser excitation of thorium‑229 nuclei inside a non‑transparent solid, detailed in Nature on December 10, 2025.
- The experiment used 148‑nanometer vacuum‑ultraviolet light to drive the nuclear transition in ThO2, a host material that is nearly opaque at that wavelength.
- Researchers detected conversion electrons from nuclear de‑excitation, demonstrating laser‑based internal conversion Mössbauer spectroscopy in a solid.
- The result expands material choices beyond VUV‑transparent crystals, enabling solid‑state studies of nuclear energy levels in engineered environments.
- Scientists frame the advance as a step toward an optical nuclear clock with prospective gains for satellite navigation, Earth observation, autonomous transport and tests of fundamental physics.