Scientists Create Quantum Sound Device That Could Transform Communications
Researchers have developed a new quantum device capable of producing controlled sound-like particles known as phonons at temperatures extremely close to absolute zero. The achievement marks an important step toward the development of phonon lasers, a future technology that could have major applications in communications, medical diagnostics, advanced sensing, and the study of new materials.
The work was carried out by researchers from McGill University and the National Research Council of Canada. The special material used in the device was produced at Princeton University.
According to Michael Hilke, Associate Professor of Physics at McGill University and co-author of the study, modern communication technologies mostly depend on light, electromagnetic waves, and electrical currents. However, in some environments, such as the ocean, sound can travel effectively where light and electrical currents cannot. Sound waves are also useful inside the human body, making phonon-based technologies promising for future medical and communication systems.
How the Device Produces Quantum Sound
The team built the device using a two-dimensional crystal that forces electrons to move through an extremely narrow channel only a few atoms wide.
When electrical current pushes the electrons through this tiny channel at very high speed, the electrons release extra energy in the form of small bursts of sound-like vibrations. These vibrations are called phonons.
Importantly, the researchers discovered that the phonons could be produced in a predictable and controllable way. This is a major requirement for future technologies that aim to use sound at the quantum level.
Why Cooling Was Important
The experiments were performed at very low temperatures, between about 10 millikelvin and 3.9 Kelvin. These temperatures are only slightly above absolute zero.
At such extreme cold, electrons behave in a more organized way, allowing scientists to observe quantum effects more clearly. In the quantum world, matter can behave like waves rather than ordinary particles.
Hilke explained that at temperatures close to absolute zero, sound is not normally produced unless electrons move together at the speed of sound or faster. Previous studies had observed related effects when electrons came close to the sound barrier. However, this new work pushed the system beyond that point.
The findings show that existing theories may need to be reconsidered, especially because electrons can become very hot even when the surrounding crystal remains extremely cold.
A Step Toward Phonon Lasers
The discovery could help scientists move closer to creating phonon lasers. Unlike ordinary lasers, which use light, phonon lasers would use controlled sound-like particles at the quantum level.
Such technology could be useful in areas where sound waves have advantages over light or electrical signals. Possible future applications include faster communication systems, more sensitive detectors, better methods for studying biological materials, and improved medical technologies.
The next stage of the research will focus on testing the device with other materials. One possible material is graphene, which could allow the system to operate at even higher speeds.
Understanding Energy in Advanced Materials
Hilke noted that phonons are difficult to generate and control, which is why researchers are exploring new physical regimes. At a broader level, the study helps scientists better understand how electrical current and energy move and transform inside advanced electronic materials.
The work provides new insight into how electrons can release energy as quantum sound waves when confined inside ultra-thin materials and driven at high speeds.
Reference
Wang, Z. T., Hilke, M., Fong, N., Austing, D. G., Studenikin, S. A., West, K. W., & Pfeiffer, L. N. (2026). Resonant Magnetophonon Emission by Supersonic Electrons in Ultrahigh-Mobility Two-Dimensional Systems.ย Physical Review Letters, 136(14). https://doi.org/10.1103/m1nb-j1h6