Scientists have developed a new method for detecting low-mass dark matter using superconducting nanowire single-photon detectors (SNSPDs) in the QROCODILE experiment.
Why it matters: This breakthrough could significantly advance our understanding of dark matter, a mysterious substance that makes up about 80% of the universe’s mass but has eluded detection so far.
The details:
- The QROCODILE experiment uses SNSPDs made of thin tungsten silicide (WSi) microwires cooled to just 0.1 degrees above absolute zero.
- In the superconducting state, electrons form pairs called Cooper pairs. When a dark matter particle collides with the nanowires, it breaks these pairs, creating a measurable electrical pulse.
- This approach allows the sensors to detect energy deposits as low as 0.1 eV, much lower than other detection methods.
- The detector’s geometry also provides directional sensitivity, which is crucial for distinguishing true dark matter signals from background noise.
During a 400-hour test run, the QROCODILE detector achieved a very low energy threshold and set new constraints on dark matter-electron scattering down to 30 keV masses.
What they’re saying:
- “The idea for the QROCODILE experiment took shape a few years ago when Ilya Charaev, an expert on superconducting nanowires, moved from MIT to Zurich,” said Laura Baudis and Andreas Schilling, part of the QROCODILE collaboration.
- “This is the first time we’ve been able to search for dark matter particles in such a low mass range, made possible by our new detector technology,” says Laura Baudis, lead author of the study.
What’s next: The research team plans to improve the detector’s sensitivity, increase its effective mass, and relocate the experiment to an underground lab to minimize background noise. They hope these enhancements will allow the QROCODILE experiment to explore new regions of light dark matter parameter space.
