A chip-scale nuclear clock could be a hundred times more precise than the atomic clocks used to run GPS today.
Modern timekeeping relies on the vibrations of electrons, which are sensitive to external interference. This new prototype uses the nucleus of Thorium-229, which is much better shielded from the environment and vibrates at a much higher frequency. Embedding these atoms into tiny photonic resonators on a chip makes the clock small enough for practical use. A nuclear clock of this size would not lose a single second over the entire age of the universe. This level of precision would enable navigation systems accurate enough to guide vehicles through centimeter-level obstacles.
Toward nanophotonic platforms for solid-state 229Th nuclear clocks
arXiv · 2604.20687
While the $^{229}$Th nuclear isomer has recently been observed and laser-excited, converting optical nuclear manipulation into a chip-scale solid-state frequency standard remains an open challenge. Here, we present a nanophotonic platform to realize an all-solid-state nuclear clock based on the low-energy isomeric transition of $^{229}$Th embedded in high-$Q$ fluoride photonic resonators. By coupling ensembles of thorium nuclei to confined optical modes, we show that resonant field build-up in t