Now physicists have managed to take a decisive step in this direction. Two research teams have succeeded simultaneously in measuring the long-sought Thorium nuclear transition, which enables extremely precise nuclear clocks. The Vienna University of Technology is part of both teams.
If you want to build the most accurate clock in the world, you need something that ticks very fast and is extremely precise. In an atomic clock, electrons are used, which can be switched back and forth between two different states in a very precisely defined way. Even more precise, however, would be a nuclear clock that does not use states of electrons, but internal states of the atomic nucleus as the clock generator. For decades, people have been searching for suitable atomic nuclei for this purpose, and for a long time it had been conjectured that a specific thorium isotope must have a nuclear state that would be suitable for the construction of a new generation of high-precision clocks. This long-sought core state of thorium has now been demonstrated experimentally for the first time. This occurred twice, by two different international research teams. The Vienna University of Technology played a significant role in both experiments. The results of the two experiments were published simultaneously in the scientific journal "Nature".
In any case, a functioning nuclear clock would furnish new findings in the search for the mysterious dark matter. Moreover, the nuclear clock could significantly improve the measurement of tiny irregularities in the Earth's gravitational field or satellite-based navigation.