First Sub-MeV Dark Matter Search with the QROCODILE Experiment Using Superconducting Nanowire Single-Photon Detectors

TL;DR

The QROCODILE experiment employs superconducting nanowire detectors to achieve the first sub-meV dark matter search, setting new constraints on low-mass dark matter interactions with directional sensitivity.

Contribution

This work introduces a novel superconducting nanowire detector setup for dark matter detection, achieving unprecedented low-energy sensitivity and directional detection capabilities.

Findings

Set new world-leading constraints on sub-MeV dark matter interactions.

Achieved energy sensitivity as low as 0.11 eV.

Demonstrated potential for directional dark matter detection.

Abstract

We present the first results from the Quantum Resolution-Optimized Cryogenic Observatory for Dark matter Incident at Low Energy (QROCODILE). The QROCODILE experiment uses a microwire-based superconducting nanowire single-photon detector (SNSPD) as a target and sensor for dark matter scattering and absorption, and is sensitive to energy deposits as low as 0.11 eV. We introduce the experimental configuration and report new world-leading constraints on the interactions of sub-MeV dark matter particles with masses as low as 30 keV. The thin-layer geometry of the system provides anisotropy in the interaction rate, enabling directional sensitivity. In addition, we leverage the coupling between phonons and quasiparticles in the detector to simultaneously constrain interactions with both electrons and nucleons. We discuss the potential for improvements to both the energy threshold and effective volume of the experiment in the coming years.