From guns to lightsabers, lasers have been powerful forces in the world of science fiction. But in reality, lasers have uses very different from the kinds of futuristic weaponry of fiction, assisting in medical procedures, a range of electronic devices, and even satellites currently involved in the search for alien life.
Now, researchers from University College London and Imperial College London have collaborated to produce a laser system that exhibits a unique kind of swarm behavior, which they have likened to a system of “living” lasers.Â
Background: Movements of Swarm Behavior
Scientists study swarm behavior to learn more about animal communication and strategy. This behavior is classified as the collective movement of the same or similar species moving either for purposes of migration or perhaps to avoid prey. Swarming is most often seen in insects like locusts, but is also observed in animals like birds or fish.
Animals like sharks can also produce deadly swarms while feasting on carcasses. Many swarm behaviors can also be characterized by mathematical models, which scientists use to try to calculate the nuances in these unique natural behaviors. Scientists have learned over time that with a mathematical base, many swarm behaviors can easily be predicted, allowing scientists to track various animal species better, and glean more from their movements.
Analysis: Making Swarming Lasers
To produce a system of swarming lasers, the researchers with University College London and Imperial College London injected titanium dioxide microparticles into a dye, and then added another special particle that had a coat of light-absorbing material on one side. After a bright light shone on the double-sided particle for a few moments, the other particles appeared to swarm, emitting light similar to that of a laser. Once the trigger light was shut off, the microparticles relaxed and ceased their laser-like actions.
The researchers tested the system with a variety of similar cues and found that the laser system adapted quickly to its environment, shifting its swarming patterns. According to the senior author of the paper and a physicist at Imperial College London, Riccardo Sapienza, “We asked ourselves if we could create a laser with the ability to blend structure and functionality to reconfigure itself and cooperate as biological materials do.”Â
Outlook: Sentience or Not?
One unique outcome of the research is that this system of swarming lasers could even challenge our existing views about sentience, of which there are already many different definitions.
One definition involves organisms that respond to environmental factors. Since the laser system actually did respond to a series of external cues, one might present the argument that it was functionally sentient. Granted, most definitions of sentience also involve awareness, feelings, and other factors which, clearly, these swarming lasers do not possess. Â
For now, since the researcher’s lasers behaved similar to biological materials, their activity will continue to raise interesting questions about the debate over sentience. As the results of this fascinating study reveal, scientists are moving closer to developing smart materials that, one day, may actually be able to think for themselves.Â
Kenna Hughes-Castleberry is a staff writer at the Debrief and the Science Communicator at JILA (a partnership between the University of Colorado Boulder and NIST). Her writing beats include deep tech, the metaverse, and quantum technology. You can find more of her work at her website: https://kennacastleberry.com/