Researchers have demonstrated a new quantum sensing technique that effectively eliminates a major source of background noise, a breakthrough that could improve future searches for dark matter and gravitational waves.

The study, published in Nature, describes a prototype device that uses two atom interferometers operating at different locations but sharing the same laser source. By comparing measurements from the two instruments, the system can cancel out laser noise that would otherwise overwhelm extremely weak signals.

To test the approach, the researchers deliberately added strong noise to the laser. The device continued to operate successfully, with measurements limited primarily by the atoms' own quantum randomness rather than external interference.

Atom interferometers measure tiny disturbances by tracking the wave-like behavior of atoms and are considered promising tools for probing fundamental questions in physics. Their sensitivity, however, has long been constrained by noise in the laser pulses used to manipulate and measure atoms.

The team also applied oscillating signals designed to mimic those expected from primordial gravitational waves and ultralight dark matter. Even when operating together under noisy conditions, the paired interferometers were able to detect the signals clearly.

Scientists say the technique could help future detectors search for faint signals from the early universe, probe the nature of dark matter, and shed light on how supermassive black holes formed less than a billion years after the Big Bang.