Photonic technologies have struggled to shrink at the same pace as electronics. The limitation comes from basic physics. The uncertainty principle links how tightly light can be confined to its wavelength, which in the visible and near-infrared range can be up to a thousand times larger than the de Broglie wavelength of electrons used in circuits. As a result, photonic chips remain relatively large, and optical imaging faces strict resolution limits.
Plasmonics once appeared to offer a solution by using metals to compress light into regions smaller than its wavelength. However, metals inevitably lose energy as heat, a drawback that has slowed progress toward efficient, scalable devices.
In 2024, a team led by Ren-Min Ma at Peking University, China reported a major advance in Nature. They developed the singular dispersion equation, a theoretical framework that explains how light can be confined to extremely small scales in lossless dielectric materials. Because this method relies only on dielectrics, it avoids ohmic losses and opens the door to more compact and energy-efficient photonic technologies.
To read more, click here.