Searches for Dark Matter with Optically Levitated Sensors

While astrophysical observations indicate that vast majority of the matter in the universe is dark matter, its detection in the laboratory remains a major outstanding challenge. The rapid development of optomechanical systems over the past few decades is now providing new tools for searching for dark matter. As such technologies reach quantum measurement regimes, they can enable new searches for extremely weakly coupled phenomena, beyond the sensitivity of known techniques. I will describe a first demonstration of a search for dark matter using an optically trapped nanogram mass sensor. This search already exceeds the sensitivity of even large underground detectors for certain classes of dark matter candidates, with only a few days of exposure. If a signal were detected, such sensors would also be able to correlate its direction with earth's motion through the galaxy, providing definitive confirmation of the astrophysical origin of the signal. Additional applications of this technology to search for dark matter candidates that may carry a small electric charge will also be described.