Direct limits for scalar field dark matter from a gravitational-wave detector

Area of Science:

• Astrophysics and Cosmology
• Particle Physics
• Quantum Optics

Background:

• The composition of dark matter remains a significant mystery in modern physics.
• Scalar field dark matter is a leading theoretical candidate, prompting exploration with sensitive instruments.
• Gravitational-wave detectors offer a novel approach for direct dark matter detection, operating beyond classical limits.

Purpose of the Study:

• To conduct a direct search for scalar field dark matter using the GEO600 gravitational-wave detector.
• To establish new constraints on the mass and coupling constants of scalar field dark matter.
• To demonstrate the utility of quantum-enhanced interferometry in dark matter searches.

Main Methods:

• Utilized the GEO600 interferometer, a gravitational-wave detector operating beyond the quantum shot-noise limit.
• Searched for characteristic signals of scalar field dark matter interacting with the interferometer's beam splitter.
• Applied data analysis techniques to exclude potential dark matter signals and set upper limits.

Main Results:

• Established new upper limits on the coupling constants of scalar field dark matter as a function of its mass.
• Achieved constraints that improve upon previous direct search limits by over six orders of magnitude.
• Obtained constraints that are up to four orders of magnitude more stringent than some equivalence principle tests.

Conclusions:

• Direct searches using gravitational-wave detectors are a viable method for investigating or constraining scalar field dark matter.
• Quantum-enhanced interferometry holds significant potential for future dark matter detection experiments.
• This research opens new avenues for exploring dark matter candidates beyond traditional methods.