Atom interferometry in a cavity-controlling residual amplitude modulation (RAM)

Prof. Holger Mueller

Atom interferometry presents a way to leverage quantum mechanics to test gravity and fundamental physics. We have recently shown that the light bound by a pair of mirrors can be used to levitate an atom in a quantum superposition of two places at once, for a macroscopic duration of time, thus realizing a stationary probe of gravity. The sensitivity of the experiment is currently limited by laser power fluctuations. This project aims to suppress noise in the laser frequency by minimizing residual amplitude modulation (RAM) arising from our electro-optic modulators (EOMs). This can potentially enable longer coherence times, as well as suppress detection noise (our largest noise source) when imaging low numbers of atoms.

This project will involve optical setup for an EOM test bench, and careful characterization of the RAM for different laser beam sizes and EOMs. The project may evolve to implementing an active RAM cancellation servo depending on student interest and project findings.