Scientists Use Light to Control Electric Currents Without Resistance

A new method for controlling electric currents with light has been unveiled in a study published in Nature this January. By using circularly polarised light, researchers can steer the flow of electrons without resistance in an advanced magnetic material. This discovery could transform how electricity is managed in high-performance computing systems.

The breakthrough centres on a material called a moiré Chern ferromagnet, formed by stacking ultrathin layers with a slight angular mismatch. In this material, electrons move freely along its edges without encountering resistance. The direction of their flow depends on the orientation of the material's magnetic field.

Traditional electric currents face resistance, which generates unwanted heat—especially in large-scale facilities like data centres and quantum computers. The new technique avoids this problem by using light to switch the magnetic field's orientation. This allows precise, wireless control over the electron flow, reducing energy loss and improving efficiency. The research not only demonstrates a way to cut power consumption in electronic devices but also opens avenues for studying other properties of moiré Chern ferromagnets. These properties could be vital for advancing quantum information processing.

The findings offer a practical solution for reducing heat in high-demand computing environments. With light-driven control of electron movement, future devices may operate with far less energy waste. The study also sets the stage for further exploration into magnetic quantum materials and their applications in next-generation technology.