A type of material that can change the path of light and other types of radiation around objects has been developed. Researchers indicate that this could be a groundbreaking solution to make objects invisible.
Two independent research teams have hypothesized how to use “metamaterials” to cloak an object, rendering it invisible to visible light, infrared light, microwaves, and even underwater detection systems. Their findings suggest that what was once considered science fiction could soon become a reality.
The idea originated from the phenomenon of refraction—where electromagnetic waves travel fastest, but not necessarily along the shortest path. This phenomenon is what makes a pencil submerged in a glass of water appear broken at the interface between water and air.
“Imagine an environment that can direct light to flow around a depression within it“, stated physicist Ulf Leonhardt from the University of St. Andrews, UK.
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Illustration of the refraction phenomenon. |
The rays of light would flow behind the object as if they were traveling in a straight line.
“Any object placed in this depression would become invisible to light. Here, the medium would create a special optical illusion: it would be invisible“, Leonhardt explained.
“It is entirely feasible to fabricate such devices. The method described here could also be used to evade detection by sound detectors or other types of electromagnetic waves“, the author added.
This theory differs from the techniques used in modern stealth devices, which reflect radar waves, preventing detection.
Instead, an object wishing to become “invisible” would be enclosed in an exterior shell made of metamaterials, creating an illusion similar to a mirage, according to David Schurig from Duke University, North Carolina, US, a member of the second research team.
Metamaterials are composite structures unlike anything found in nature. They are designed to have unusual properties, such as the ability to bend light in unique ways.
The research team at Duke has begun the process of fabricating this material.
T. An
