Dark matter accounts for 85% of the matter in the universe, but scientists still do not know what it is made of. A study, published in Physical Review Letters, by Rice University researchers proposes a detector design that could help search for axions, hypothetical particles that many physicists think could make up dark matter.

The proposed detector would rely on a class of semiconductor materials whose response changes when their orientation shifts within a magnetic field. This material response makes it easier to tune the detector, allowing researchers to probe a range of axion masses that have remained difficult to explore with existing technologies.

“We are proposing a well-studied material from condensed matter physics for a new application—axion detection,” said Jaanita Mehrani, a doctoral student in Rice’s Applied Physics Graduate Program who is the first author on the study. “What’s different about this material is that it doesn’t have to use complex mechanical tuning mechanisms, it simply tunes with the magnetic field.”

Everything around us, from atoms and molecules to planets and galaxies, is governed by two extraordinarily successful theories of physics: quantum mechanics and gravity. Quantum mechanics explains the behavior of the microscopic world, while Einstein’s theory of gravity describes the motion of stars, black holes and the expansion of the universe. Yet despite their successes, physicists are still searching for a theory of “quantum gravity” that would unite them into a single description of nature.

One of the most widely expected features of such a theory is that gravity should obey the laws of quantum mechanics. And this is where it gets difficult: Quantum mechanics predicts that any object can be delocalized over multiple places at once, which is routinely tested in experiments with atoms and even small clumps of metal. Gravity, according to Einstein’s theory, is space and time itself—it can be curved, flat or even have waves propagating through it, as confirmed by gravitational wave detectors. So many physicists believe that spacetime around a quantum object would also exist in multiple “states” simultaneously.

But what would such a situation actually look like?