Researchers from ITMO University, along with colleagues from Sweden, Australia, the United States and Lithuania, have discovered Fano resonance in perovskite nanoparticles and gained control over the resonance spectrum for an array of inorganic nanoparticles. This newly designed method reversibly adjusts the radiation color of nanosized light sources. Previously, radiation color could be specified only during nanoparticle synthesis, but now it can be changed after synthesis. Stability and electromagnetic resonances of the particles are retained during this adjustment. This makes them promising for optical chips, LEDs and optoelectronic devices.
Resonance is the coincidence between frequencies of two oscillations increasing their intensity. A half-century ago, the Italian theoretical physicist Hugo Fano described a special type of resonance with an asymmetric profile arising from the interference of two wave processes. Since then, Fano resonance has been actively used in photonics, for example, to create fast optical switches. The reduction of such switches to nanoscale will dramatically increase the performance of photonic chips by integrating a huge number of elements in one device.
