Jez's Blog

If you have watched or read Harry Potter, you will then know the invisibility cloack which Harry recieves as a Christmas present in his first year in Hogwarts. According to BBC News, Invisibility cloak closer with flexible 'metameterial', scientists in the UK have demonstrated a flexible film that represents a big step toward the "invisibility cloak," made famous by Harry Potter. The film contains structures that form a "metamaterial," an artificial material engineered to provide properties which may not be readily available in nature, which can manipulate light to make objects invisible.

A metamaterial usually gain their properties from structure rather than composition, using the inclusion of small inhomogeneities (having a various structure throughout) to enact effective macroscopic behavior. The research in metamaterials involves such fields as electrical engineering, electromagnetic, solid state physics, microwave and antennae engineering, classic optics, etc.

In a work of metamaterial research, demonstrations of invisibility have occurred in light waves with a much longer wavelength -- a far redder color -- than we can see. This is considered as the most striking demonstrations of invisibility. However, this requires metamaterials with relatively large structures, which makes it easier to construct. Hense, the chanllage of creating a demonstration of invisibility for far shorter waves that we can see is that a metameterial requires its nanostructures - structures so tiny that they make manufacturing very difficult.

"The first step is imagining fist of all that this could be done," said Andrea Di Falco of St. Andrews University, the author of the New Journal of Physics.

Ortwin Hess, a physicist who recently took up the Leverhulme Chair in Metamaterials at Imperial College London, called the work "a huge step forward in very many ways". "It clearly isn't an incisibility cloak yet -- but it's the right step toward that," Hess told BBC News. He also added that the next stept woild be to characterise the way that the material's opical properties change as it is bent and fold; if the properties were sensitive to movement, the films may be useful for next-generation lenses; otherwise, if the properties were inpervious to bending and motion, then the film might be useful in contact lenses. "Harry Potter has to wait still - that's the huge goal," he said.

After reading the article, I have come up with two conclusions: first of all, it is that sometimes what matters is not the result in the end, but what may be gained through out the process of approaching the final goal. We do not know if an invisibility cloak could be actually invented, but at least we know that the film may be useful for several other things in the future.; and second, it is that we might not need to travel in the speed of light to be invisible.