All matter with which you have ever interacted has mass, and as such, obeys the universal laws of motion , enunciated by Isaac Newton centuries ago. If you push something, it will move in the direction in which you push it. However, matter with negative mass would do the opposite. Instead of reacting in a predictable manner when force is applied, objects with a negative mass react contrary to what might be expected. What seems so unusual to us has become reality, since a team of researchers from the University of Rochester (USA) has devised a way to create negative mass particles using lasers.
Experts have created particles with negative mass in an atomically thin semiconductor, causing it to interact with light confined in an optical microcavity.
This is only “interesting and exciting from a physical perspective, but it also turns out that the device we have created has a way of generating laser light with an incrementally small amount of energy,” says Nick Vamivakas, associate professor of quantum optics and quantum physics at the Optical Institute of Rochester to the journal Nature Physics.
The device consists of two mirrors that create an optical microcavity, which confines the light in different colors of the spectrum depending on how the mirrors are spaced. The experts embedded an atomically thin molybdenum diselenide semiconductor in the microcavity.
The semiconductor was placed in such a way that its interaction with the confined light resulted in small particles of the semiconductor called excitons, which were combined with photons of the confined light to form polaritons (particles born of light and matter).
“By making an exciton give part of its identity to a photon To create a polariton, we end up with an object that has a negative mass associated with it. That’s something to think about, because if you try to push or pull, it will go in the opposite direction to what your intuition would tell you.”
Other research groups have been experimenting with similar devices, but this is the first device in producing particles with negative mass.
Although applications are still to come, this lab will continue to explore, for example, how this device could serve as a substrate to produce lasers. “With the polaritones that we have created with this device, the prescription to operate a laser is completely different,” says Vamivakas. “The system starts to work with a much lower energy input ” than the traditional lasers that are currently used.
Another area of research would be the physical implications of creating negative mass in the device. “We are dreaming of ways to apply the push-pull motion, perhaps by applying an electric field through the device, and then studying how these polaritons move in the device under the application of external force,” concludes Vamivakas.