Scientists unlock new magnetic component in the faraday effect after two centuries

Faraday Effect in optics and quantum tech. (Image: Enrique Sahagún)

Researchers at Hebrew University discovered a hidden magnetic component in light. This study changes the understanding of the Faraday Effect after two centuries. It shows light’s magnetic field can influence matter directly. The discovery challenges assumptions that only the electric field matters.

Who made the discovery?

The team was led by Amir Capua and Benjamin Assouline. They combined theoretical modelling with analysis of real crystal materials. Their focus was Terbium Gallium Garnet, widely used in optics. This material allowed precise calculation of magnetic contributions from light.

Where did it take place?

The research was carried out in Jerusalem, Israel. Experiments and modelling explored interactions within crystal materials. Findings have global relevance for photonics, spintronics and quantum technologies. The results apply to both visible and infrared wavelengths.

The discovery revises assumptions dating back to Michael Faraday’s 1845 work. Faraday first observed the effect that rotates light in a magnetic field.

How did they find it?

Researchers used the Landau–Lifshitz–Gilbert equation for modelling. They showed the magnetic field generates torque inside the material. Their calculations revealed wavelength strongly affects the magnetic contribution.

The team found the magnetic field contributes up to seventy percent. Traditionally, only the electric field of light was considered active. In visible wavelengths, it accounts for about seventeen percent.

This opens possibilities for new optical and magnetic applications. It could transform technologies including data storage and quantum devices.

The bigger picture

The discovery shows light does more than illuminate matter. Its magnetic field actively interacts with material at a microscopic level. Future research may exploit this in advanced optics and quantum tech.