Physicists at the Massachusetts Institute of Technology (MIT) created the world's first perfect mirror. When hit on a smooth surface, light waves (or other waves, for example, acoustic) are reflected perfectly, that is, without distortion. The new technology may find application in the production of solar cells, lasers, fiber optic networks and other areas where light reflection is used.
The experiment used ordinary mirrors. Everything is very simple: mirrors do not let light through (as well as sound, water or radio waves), causing it to reflect. As you know, nothing is reflected perfectly, part of the energy is always absorbed by the material or scattered in different directions. For reflective lasers, solar installations, or fiber optic networks several hundred kilometers long, barely noticeable deviations from ideality can significantly affect efficiency.
The perfect mirror was discovered almost by accident. A group of researchers led by MIT professor Marina Solyachich studied the behavior of a photonic crystal, in particular, a ridged silicon wafer coated with a silicon nitride nanolayer. The holes of the plate were so small that only one light wave was transmitted. As expected, at many angles the photonic crystal partially absorbed light. However, when incident at an angle of 35 degrees, a light wave of a certain length was ideally reflected from the surface of the crystal. Each photon emitted by a light source is reflected at the right angle. No absorption or dispersion has occurred.
The effect was unexpected. A similar phenomenon was described by mathematician John von Neumann in 1929, but was never demonstrated experimentally.
This is a completely different way to control the light. The mirror really perfectly reflects the light, ”says Yale University professor Douglas Stone, who was not involved in the study.
A few days earlier, scientists from the University of Darmstadt intentionally turned off the light for one minute.
The article is based on materials .
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