Program overview

Quantum theories of physics have played a pivotal role in science and technology. Much of our understanding of nature is embodied by the standard model of particle physics, the overarching relativistic quantum field theory. Its theoretical predictions have been successfully compared with experimental results at astounding levels of precision (currently at the parts-per-trillion level and better). Quantum theories also form the basis of a revolution that is currently unfolding in science, driven by the development of technology whose primary principle of operation is based on the laws of quantum mechanics. Examples include quantum computers, which promise to completely outperform their classical counterparts, and quantum cryptography, which can potentially deliver completely secure communication. Notwithstanding these successes, quantum theories are faced with a number of challenges. For example, the measured magnetic moment of the muon particle deviates significantly from standard-model predictions. Moreover, astronomical observations suggest that the universe is filled with dark matter and dark energy, phenomena for which the standard model offers no explanation. In this context it is worth noting that in the past, precise spectroscopic measurements of simple atomic and molecular systems have repeatedly led to ground-breaking discoveries of (then unknown) quantum phenomena (such as quantum electrodynamics). Also today, simple atoms and molecules form promising systems for tests of the validity of the standard model as well as searches for yet undiscovered particles and interactions. However, current ‘classical’ spectroscopic methods are running out of steam to provide the sensitivity and precision needed to test present and future standard-model predictions. In this research program, we will exploit the opportunities offered by cutting-edge quantum technologies to boost the sensitivity of tests of the standard model at the atomic and molecular scale by orders of magnitude. To this end, we will use the working principle of the trapped-ion quantum computer to dramatically enhance measurement capabilities in precision spectroscopy with immediate applications in fundamental physics, quantum chemistry, and quantum many-body physics. In particular, we will develop and perform highly sensitive and accurate quantum enhanced spectroscopy that overcomes many of the limitations of present-day spectroscopic techniques, and use it to measure the energy-level structure of some of the simplest (calculable) composite systems in nature: the two-body atomic helium ion and the three-body molecular hydrogen ion. We will compare the results with precise theoretical predictions, thus achieving 10-100 times more stringent tests of the standard model, and improved values of fundamental physical constants. Moreover, quantum-enhanced spectroscopy of the various atomic and molecular degrees of freedom that will become accessible through this program will establish a sensitive and versatile quantum sensor that could detect (or rule out) possible anomalies in the interactions between electrons, nuclei, and nucleons, which might arise from yet undiscovered physics beyond the standard model. Such a quantum-engineered ‘new-physics sensor’ may thus help answer pressing questions in contemporary physics regarding the ultimate validity of the standard model, and the nature of the elusive dark matter that fills 27% of our universe.