A CNRS-led international team has uncovered a way to generate an electron gas – typically found in LED screens – simply by shining light on a layered oxide material. When the illumination ceases, the electron gas vanishes. This reversible effect at the intersection of optics and electronics marks a step toward components that could one day be operated entirely by light.
Such light-controlled devices could revolutionize electronics by offering faster, more energy-efficient operation. For instance, optical transistors may reduce by up to one-third the number of electrical contacts required on a processor chip, saving billions of connections and streamlining circuitry.
The study also points to hybrid photonic-electronic technologies such as ultra-sensitive optical detectors, where light dramatically amplifies current flow – up to 100,000 times greater than under dark conditions for the same voltage.
Researchers achieved the breakthrough through atomic-level precision. They fine-tuned the atomic arrangement at the oxide interface, used atomic-scale imaging to observe behavior under illumination, and employed theoretical modelling to map the motion of electrons triggered by light.
Research Report:Giant photoconductance at infinite-layer nickelate/SrTiO3 interfaces via an optically induced high-mobility electron gas.
