Windchime and POLONAISE: New directions in dark matter direct detection with quantum sensing

Attempts to directly detect dark matter have been “successful failures”: while they have effectively probed vast amounts of parameter space for WIMPs and axions, they have yet to yield significant insights into dark matter’s properties. As our prior dark matter models have loosened, rapid advances in quantum sensing technology raise an important question: Are there previously untestable dark matter models that we now have unique sensitivity to? Over the past few years, a collaboration of theorists, dark matter experimentalists, and quantum sensing experts, known as the Windchime Project, has been working to answer this question. Emerging from this project, we have identified two unique approaches to dark matter searches utilizing resonators for ultraheavy and ultralight dark matter.

Windchime MEMS: We are developing optomechanical sensors to search for ultraheavy dark matter (UHDM) tracks in sensor arrays. These mechanical sensors incorporate a test mass that is perturbed by subtle gravitational interactions between UHDM particles and ordinary matter, resulting in measurable signals. By employing quantum-enhanced impulse sensing, Windchime will test ultraheavy dark matter candidates with masses near the Planck mass (10¹⁴ GeV), including models such as WIMPzillas, quark nuggets, and black hole relics. I will discuss the ongoing sensor development and our sensitivity to heavy dark matter models.

POLONAISE: We have also conducted the first search for ultralight dark matter using a magnetically levitated particle. In this experiment, a sub-millimeter permanent magnet was levitated in a superconducting trap with a measured force sensitivity of 0.2 fN/√Hz. Although we found no evidence of a signal, we derived limits on dark matter coupled to the difference between baryon and lepton number (B - L) in the mass range (1.10360−1.10485)×10⁻¹³ eV c⁻². Our most stringent limit on the coupling strength is g < 2.98×10⁻²¹. I will outline our plans for the POLONAISE (Probing Oscillations using Levitated Objects for Novel Accelerometry In Searches of Exotic Physics) experiment, which includes short-, medium-, and long-term upgrades aimed at achieving leading sensitivity across a wide mass range, demonstrating the promise of this novel quantum sensing technology in the search for dark matter.