A team of researchers, publishing their results in the professional journal of the American Physical Society (APS), has identified three quantum compounds with unusual electronic properties that are calculated to increase the sensitivity of future dark matter detectors by up to a thousand times. This was reported by RBC-Ukraine with reference to the respective scientific study. According to the authors' estimates, the discovery goes beyond these specific three compounds and points to the existence of an entire class of materials suitable for creating ultra-sensitive experimental setups of a new generation.
Why dark matter is almost impossible to detect
According to astrophysicists' estimates, dark matter makes up about 85 percent of all matter in the universe. At the same time, it does not emit, absorb, or reflect light, making it invisible to traditional optical and radio telescopes. Modern ground-based and underground detectors attempt to capture tiny bursts of energy that occur when dark matter particles collide with ordinary matter. However, for light particles, the energy transfer is so meager that standard materials used in operating installations are simply unable to register it. It is precisely this technological sensitivity "ceiling" that became the starting point for the search for new materials with fundamentally different electronic characteristics.
Quantum-mechanical modeling and the selection of three compounds
The researchers performed quantum-mechanical modeling and based on it identified three compounds capable of capturing weak signals that remain unnoticed by existing detectors. The key factor determining the choice was the presence in these materials of plasmons—collective electronic pulses that respond to extremely small energy inputs and amplify the signal. It is this property that makes it possible to overcome the threshold below which standard crystal structures are unable to react to interaction with a dark matter particle.
Titanium diselenide: potential 100–1000 times higher than existing analogues
According to the researchers' calculations, titanium diselenide (TiSe₂) could turn out to be 100–1000 times more sensitive than existing materials used in dark matter detectors. An additional advantage of this compound is its suitability for mass production, which significantly simplifies the task of scaling experimental setups. Two of the three studied materials are characterized by directional sensitivity: the detector's response depends on the angle at which the dark matter particle enters the crystal lattice.
Diurnal fluctuations as a tool to filter out background noise
The directional sensitivity of two of the three compounds opens up an additional method of signal verification. Since the Earth is constantly rotating, the orientation of the detector relative to the dark matter flux changes throughout the day. This allows scientists to observe regular daily fluctuations of the signal and thereby clearly distinguish potential dark matter from random background noise. Such an approach significantly increases the statistical significance of any detected event and reduces the probability of false positives.
Not three compounds, but an entire class of materials
The authors of the study emphasize that the search should not be limited to just the three identified compounds. Their discovery confirms the existence of an entire class of quantum materials that can become the basis for creating new ultra-sensitive experimental installations. This means that in the coming years, an expansion of the list of candidates is expected, and likely the appearance of detector prototypes using plasmonic signal amplification mechanisms. For dark matter science, which for decades has faced the problem of insufficient instrument sensitivity, such a shift in materials science could become one of the key factors determining the success of future experiments.
