Light Switch For Electronics Design

By harnessing light to command electrons, this discovery hints at a new era of hybrid photonic-electronic devices—where circuits don’t just conduct electricity but glow with speed.

Credit: CC0 Public Domain

An advancement that blurs the boundaries between optics and electronics, scientists have discovered how to create and manipulate an electron gas using light—a feat that could revolutionize the way future chips and quantum devices operate.Researchers from the Strasbourg Institute of Materials Physics and Chemistry and the Solid State Physics Laboratory at Université Paris-Saclay collaborated on the work, combining experimental and computational insights.

The international team, led by researchers at the Albert Fert Laboratory (CNRS/Thales), has shown that illuminating a carefully engineered oxide structure can generate a two-dimensional electron gas, a phenomenon typically found in semiconductor interfaces like those in LED screens. When the light source is switched off, the gas vanishes—demonstrating precise, reversible control over the electronic state of the material.

This discovery marks the first time such an electron gas has been triggered solely by light rather than by electrical signals. The implications could be transformative: electronic components driven by photons instead of electrons promise unprecedented speed, lower energy consumption, and reduced circuit complexity.

For instance, if light could replace even part of the electrical wiring in microprocessors, it might eliminate nearly one-third of the chip’s electrical contacts—potentially saving billions of connections across a single processor. The result: faster computing, lower heat generation, and leaner manufacturing processes.

Beyond faster processors, the research points to applications in spintronics and quantum computing—fields where controlling electronic behavior with precision is critical. It could also lead to ultra-sensitive optical detectors that exploit this effect, where light dramatically amplifies electrical current by up to 100,000 times compared to dark conditions.

The team achieved the feat through meticulous tuning of the atomic interface between two oxide layers. Advanced microscopy revealed how atoms responded under illumination, while theoretical models mapped the resulting electron dynamics.