Invisibility Cloak Closer

Posted on August 11, 2008  Comments (2)

Invisibility shields one step closer with new metamaterials that bend light backwards

Applications for a metamaterial entail altering how light normally behaves. In the case of invisibility cloaks or shields, the material would need to curve light waves completely around the object like a river flowing around a rock. For optical microscopes to discern individual, living viruses or DNA molecules, the resolution of the microscope must be smaller than the wavelength of light.

The common thread in such metamaterials is negative refraction. In contrast, all materials found in nature have a positive refractive index, a measure of how much electromagnetic waves are bent when moving from one medium to another.

In a classic illustration of how refraction works, the submerged part of a pole inserted into water will appear as if it is bent up towards the water’s surface. If water exhibited negative refraction, the submerged portion of the pole would instead appear to jut out from the water’s surface.

For a metamaterial to achieve negative refraction, its structural array must be smaller than the electromagnetic wavelength being used. Not surprisingly, there has been more success in manipulating wavelengths in the longer microwave band, which can measure 1 millimeter up to 30 centimeters long.

Related: Engineering Harry Potter’s Invisibility CloakUC-Berkeley Course Videos now on YouTubeposts on university based researchBerkeley tagged posts

2 Responses to “Invisibility Cloak Closer”

  1. Tim
    August 12th, 2008 @ 2:47 pm

    There are surely many applications for this technology when they achieve it. My concern is that it will cost so much to use and be so restricted by the government, it will only be used for nefarious purposes and will never be seen ( I know, bad pun!) except in the hands of the army or government.

  2. Jack
    October 19th, 2008 @ 11:18 pm

    This is a very interesting theory, But I also believe what the above commenter says, It will be restricted to the army and the goverment.
    I can understand why as it could be a very dangerous “item/object” if its acheive and created.

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