Searching for Vector Dark Matter with an Optomechanical Accelerometer.

TLDR: It is argued that sensitivity to vector B-L dark matter can exceed that of the Eöt-Wash experiment in integration times of minutes, over a fractional bandwidth of ∼0.1% near 10 kHz.

Abstract: We consider using optomechanical accelerometers as resonant detectors for ultralight dark matter. As a concrete example, we describe a detector based on a silicon nitride membrane fixed to a beryllium mirror, forming an optical cavity. The use of different materials gives access to forces proportional to baryon ($B$) and lepton ($L$) charge, which are believed to be coupling channels for vector dark matter particles (``dark photons''). The cavity meanwhile provides access to quantum-limited displacement measurements. For a centimeter-scale membrane precooled to 10 mK, we argue that sensitivity to vector $B\ensuremath{-}L$ dark matter can exceed that of the E\"ot-Wash experiment in integration times of minutes, over a fractional bandwidth of $\ensuremath{\sim}0.1%$ near 10 kHz (corresponding to a particle mass of ${10}^{\ensuremath{-}10}\text{ }\text{ }\mathrm{eV}/{\mathrm{c}}^{2}$). Our analysis can be translated to alternative systems, such as levitated particles, and suggests the possibility of a new generation of tabletop experiments.