Project Grant 2608249

The National Science Foundation Division of Physics awarded Amherst College, Trustees Of $625,000 on August 1, 2026, under the Mathematical and Physical Sciences program (CFDA 47.049) to investigate laser-driven vibrational transitions in molecular ions as a platform for optical molecular clocks sensitive to fundamental physical constants.

The project develops molecular vibrations in diatomic oxygen molecular cations as quantum sensors, focusing on the ground-to-excited vibrational state transition. This transition exhibits a narrow natural linewidth, high sensitivity to changes in fundamental physical constants such as proton-to-electron mass ratios, and long-term potential as an optical molecular clock. The nonpolar nature of the molecule suppresses systematic shifts from electric field effects, including AC Stark shifts and blackbody radiation. The work advances quantum information science through development of molecular vibration as a quantum sensor of time and improvements in techniques for trapping and controlling quantum states of individual atoms and molecules. The research seeks to detect variations predicted by models of quantum gravity or dark matter.

Work is performed in Amherst, Massachusetts, with a period of performance from August 1, 2026, through July 31, 2029. Undergraduate students participate as key contributors to all aspects of research, and the project supports the career advancement of a postdoctoral scholar, developing experimental and technical skills applicable across scientific careers.