Related Experiment Video
Updated: Jan 20, 2026
Reflection; Refraction; Snell's Law and Total Internal Reflection
Published on: April 30, 2023
Nonreciprocal Refraction of Light in a Magnetoelectric Material
1Department of Advanced Materials Science, The University of Tokyo, Kashiwa 277-8561, Japan.
Abstract:
In magnetoelectric materials, where the time-reversal and space-inversion symmetries are simultaneously broken, optical properties can differ between the opposite propagation directions of light. We report on an experimental observation of nonreciprocal trajectory of a light ray in magnetoelectric material CuB_{2}O_{4}. The light is refracted in different ways between the opposite propagation directions of light. We find a nonreciprocal refraction at the interface between a matter with macroscopic toroidal moment and vacuum. The resultant nonreciprocal deflection of the light is 0.005 deg, which is quantitatively explained using Fermat's principle.
Related Concept Videos
Reflection and Refraction
Light travels at different speeds depending on the material through which it is propagating. When light travels from one material to another, it will either slow down or speed up. In order to conserve energy and momentum, the light must change the direction in which it propagates. This bending of light is known as refraction. Some fraction of...
09:54Fabrication of Refractive-index-matched Devices for Biomedical Microfluidics
11:57Measuring Spatially- and Directionally-varying Light Scattering from Biological Material
05:36Subjective Refraction Test Using a Smartphone for Vision Screening
Influence of Earth's Curvature and Atmospheric Refraction on Leveling

