- Sept. 16, 2024, 2:00 am US/Central
- Yufeng Du, Caltech
Atom interferometry experiments have unique advantages in searching for various kinds of dark matter (DM). In this talk, I will introduce effects in such experiments from light DM scattering and from gravitational field of a macroscopic DM. First we discuss sensitivities of matter wave interferometers to a light DM subcomponent at sub-GeV masses through decoherence and phase shift from spin-independent scatterings. We also estimate effects from astro-particle backgrounds in the solar neighborhood, which suggests the need for shielding in space-based experiments. We then explore capabilities of atom gradiometers as accelerometers, which can be sensitive to macroscopic DM through gravitational interactions. We present a simple gauge-invariant framework for calculating leading order phase shifts in atom gradiometers under generic metric perturbation, with which we derive the signals from gravitationally interacting macroscopic DM. Future missions such as AEDGE could potentially constrain macroscopic DM fractions to less than unity for DM masses around M ∼ 10^6 kg.