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Updated: Sep 18, 2025

Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Motors based on photo-magnetic materials
Boris Kichatov1,2, Vladimir Sudakov1,2, Alexey Korshunov1,2
1Semenov Federal Research Central for Chemical Physics, Moscow 119991, Russia.
Abstract:
Absorption of light by a substance does not change its magnetic properties. However, if redox reactions occur on the surface of a material when irradiated with light and a current loop is formed, it turns into a magnet. This study reports a method for producing a new type of material-photo-magnets, which are capable of changing their magnetic properties when exposed to light. The simplest photo-magnet is a bimetallic plate made of two dissimilar metals, one part of which is coated with a semiconductor material-zinc oxide-and it is immersed in a solution of hydrogen peroxide. When exposed to light, holes and electrons are formed in the semiconductor, which take part in redox reactions during the decomposition of hydrogen peroxide. Since a current loop is formed in this case, the photo-magnet becomes a source of a magnetic field. In addition, any loop with current in a non-uniform magnetic field is affected by a force whose nature is determined by the action of the Lorentz force on moving charges. Therefore, on the basis of photo-magnets, it is possible to create motors that will move in a non-uniform magnetic field when irradiated with light.
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