New Constraints on Dark Photon Dark Matter with Superconducting Nanowire Detectors in an Optical Haloscope

Understand

Uncovering the nature of dark matter is one of the most important goals of particle physics.

• Light bosonic particles, such as the dark photon, are well-motivated candidates: they are generally long-lived, weakly-interacting, and naturally produced in the early universe.
• In this work, we report on LAMPOST (Light $A'$ Multilayer Periodic Optical SNSPD Target), a proof-of-concept experiment searching for dark photon dark matter in the eV mass range, via coherent absorption in a multi-layer dielectric haloscope.
• Using a superconducting nanowire single-photon detector (SNSPD), we achieve efficient photon detection with a dark count rate (DCR) of $\sim 6\times10^{-6}$ counts/s.