Dreissen and her colleagues are searching for a very small effect in atoms that tells us something about one of the fundamental forces of nature, the weak interaction. "The tiny effect we're looking for is a defect of one of the fundamental symmetries in physics: parity," says Dreissen. "A violation of this symmetry means that the laws of nature behave slightly differently when you look at them in a mirror. By accurately measuring this effect, we can test the Standard Model of particle physics and perhaps find clues to new particles or forces, such as mysterious 'dark' particles that may also be related to dark matter.”
Barium
The researchers hope to measure this effect for the first time in the barium atom, and with greater precision than ever before. This will allow them to verify whether the current theory still holds, or whether subtle differences emerge that point to unknown physics. They also expect to learn more about the structure of atomic nuclei, which is crucial for better understanding extreme stars like neutron stars.
Quantum trick
Dreissen: “We use charged barium ions, which we first capture and cool to near absolute zero, allowing us to monitor them in great detail. Then we apply a clever quantum trick: we quantum-entangle the ions in a special state that is immune to external interference. This allows us to reliably measure a very weak signal, normally drowned out by noise.” This approach makes it possible for the first time to observe and study the effect of parity violation in a single captured atom more accurately than ever before.
Fundamental science and technological progress
With this project, Dreissen and her fellow researchers will use cutting-edge quantum technology to find answers to pressing open questions in fundamental physics. They will combine fundamental science with technological progress. Dreissen: "With this special quantum technology, we can, for the first time in twenty years, perform the first independent, low-energy test of a significant part of the Standard Model. This will potentially enable us to discover new physics that is internationally competitive with major institutes like CERN, and expand our knowledge of atoms and nuclei. We will also develop new quantum technology that can later be used for secure communication or sensitive measurement equipment."
ERC Starting Grant
The ERC uses its Starting Grants to support talented early-career researchers in conducting groundbreaking projects for a period of five years. Dreissen receives a grant of approximately €2 million. A total of 478 early-career researchers have been awarded ERC Starting Grants.