Search for Ultralight Dark Matter with a Frequency Adjustable Diamagnetic Levitated Sensor

Among several dark matter candidates, bosonic ultra-light (sub-meV) dark matter is well motivated because it could couple to the Standard Model and induce new forces. Previous MICROSCOPE and Eöt–Wash torsion experiments have achieved high accuracy in the sub-1 Hz region. However, at higher frequencies there is still a lack of relevant experimental research. We propose an experimental scheme based on the diamagnetic levitated micromechanical oscillator, one of the most sensitive sensors for acceleration sensitivity below the kilohertz scale. In order to improve the measurement range, we utilize a sensor whose resonance frequency ω₀ could be adjusted from 0.1 Hz to 100 Hz. The limits of the coupling constant g_B–L are improved by more than 10 times compared to previous reports, and it may be possible to achieve higher accuracy by using the array of sensors in the future.