By mimicking the properties of living systems, self-organizing lasers could lead to new materials for sensing, computing, light sources and displays.
Although many synthetic materials have advanced properties, there is a long way to go to combine the versatility and functionality of materials that can adapt to their situation. For example, bone and muscle in the human body constantly reorganize their structure and composition to better accommodate changing weight and activity level.
Now, researchers from Imperial College London and University College London have demonstrated the first spontaneously self-organizing laser device, which can reconfigure itself when conditions change.
The discovery, reported in Nature Physics, could help enable the development of smart photonic materials that have properties that better mimic biological matter, such as responsiveness, adaptation, self-healing and collective behavior.
Co-lead author Professor Riccardo Sapienza, from the Department of Physics at Imperial, said: “The lasers that power most of our technologies are made from crystalline materials that have precise and stable properties. We asked ourselves if we could create a laser with the ability to combine structure and functionality, to reconstruct itself and To cooperate as biological materials.
“Our laser system can reconstruct and collaborate, thus enabling a first step toward simulating the ever-evolving relationship between the unique structure and activity of living materials.”
Lasers are devices that amplify light to produce a special form of light. The team’s experiment involved self-assembling lasers consisting of microparticles dispersed in a liquid with high ‘gain’ – the ability to amplify light. Once enough of these microparticles are collected together, they can use external energy to ‘lase’ – produce laser light.
An external laser was used to heat a ‘Janus’ cell (a cell coated on one side with a light-absorbing material), around which the microparticles were collected. The lasing created by these microparticle clusters can be turned on and off by changing the intensity of an external laser, which controls the size and density of the cluster.
Demonstrating the adaptability of the system, the team also showed how the lasing cluster could be transferred into space by heating various Janus particles. Janus particles can also cooperate, creating clusters that have properties beyond the simple addition of two groups, such as changing their shape and increasing their lasing power.
Co-lead author Dr Giorgio Volpe, from the Department of Chemistry at UCL, said: “Nowadays, lasers are used as a course in medicine, telecommunications and even industrial production. Incorporating lasers with life-like properties could lead to robust, autonomous and durable next-generation materials and sensing applications, non-traditional computing , developing novel light sources and devices for displays.
Next, the team will study how to improve the lasers’ autonomous behavior to make them more lifelike. A first application of the technology could be for next-generation electronic inks for smart displays.