Researchers at Peking University have discovered narwhal-shaped wavefunctions that trap light at scales far smaller than previously possible using only dielectric materials. The breakthrough, detailed in a 2025 paper, avoids the energy losses common in metal-based approaches. It opens paths to more efficient photonic devices and advanced imaging.
Physicists led by Ren-Min Ma developed the singular dispersion equation to enable extreme light confinement without metals. In experiments, they created a three-dimensional singular dielectric resonator that achieved a mode volume of 5 × 10-7 λ3. Near-field scanning confirmed the predicted power-law enhancement near the singularity and exponential decay at larger distances, matching both theory and simulations.