For a very long time, the idea of invisibility has enticed several scientists and led them to intensive research in material engineering. Time and again, different techniques have been proposed to achieve invisibility, but none of them have worked out quite yet.
However, a new research work published in the Nature Science Journal under the title “Multilayer homogeneous dielectric filler for electromagnetic invisibility,” suggests a new approach to making objects invisible.
But it isn’t anything like Harry Potter’s cloak that would make us invisible. It rather seems to work like H.G. Wells “The Invisible Man,” where the iconic character injects himself with a special formula to reach a state of transparency.
On the similar lines, this study investigates the electromagnetic properties of specific materials called “filler materials” that can make certain objects invisible.
The team, led by Alberto Serna and Luis Molina of the University of Extremadura in Spain, came up with the idea of using artificial materials — also known as metamaterials to induce invisibility.
These materials have high dielectric or magnetic constants and introducing them to the interiors of an object would induce invisibility.
Serna says, “The majority of the techniques with which cloaks of invisibility are developed harness the extraordinary properties of certain materials to make light circumvent the object to be made invisible.”
But this concept cannot be applied to fillers because the object will be exposed to the light and therefore forced to interact with it.
Instead, they devised a new technique called plasmonic cloaking, “which makes the object and the filler jointly invisible.” The advantage of this method is that it achieves invisibility from the inside without using any external device.
What’s more significant is that it would also allow the object to interact with its environment without being obstructed by external cloaking.
Right now, this method is valid for objects of small size as the bandwidths achieved are still narrow. However, researchers believe that the idea is quite promising and there is still a lot of scope for improvements.