By Hamish Johnston
Our very own New Journal of Physics has just published a special issue on cloaking and transformation optics — a subject dear to our hearts here on physicsworld.com.
The first article in issue — by cloaking wizards Ulf Leonhardt and David Smith — begins with a quote from the late Arthur C Clarke that sums the field up nicely. “Any sufficiently advanced technology is indistinguishable from magic”.
So, what kind of magic has been unveiled in the (virtual) pages of this special issue?
There’s a paper entitled An acoustic metafluid: realizing a broadband acoustic cloak and another called A homogenization route towards square cylindrical acoustic cloaks.
Most papers have fantastic illustrations of how the cloaks work…Er, did I say “work”? The truth is only two out of 19 papers present experimental results — the rest are mostly proposals for new ways of cloaking or new ways of using mathematics to describe cloaking.
However, as Leonhardt and Smith point out, “The engineers have been developing new materials with extraordinary electromagnetic properties”. So it shouldn’t be long before at least some of the ideas presented in this special issue become reality.