Harry Potter's invisibility cloak can do analog computing, claim researchers
It doesn't take a spell from Dumbledore or Harry Potter's invisibility cloak to make things invisible in the real world. It takes the science of making metamaterials do their wonders. A new research by experts looks into how these materials that made invisibility cloaks possibly do mathematical computations.
The team led by University of Pennsylvania electrical engineering professor Nader Engheta has looked into the possibility of computational metamaterials that will change the shape of a lightwave instead of just bending around objects.
The proponents of the research titled "Performing Mathematical Operations with Metamaterial" have published the results of their study in the journal Science.
"We introduce the concept of metamaterial analog computing, based on suitably designed metamaterial blocks that can perform mathematical operations (such as spatial differentiation, integration, or convolution) on the profile of an impinging wave as it propagates through these blocks," the abstract of the study read.
Analog computers are simpler than the digital computers that we have today. To put it simply, the latter are well-designed to do multiple tasks at the same time while the former has an architecture to achieve a single purpose.
Metamaterials that can do analog computing can be used for edge detection and will be more efficient than digital computers that need to convert what it receives into bits.
"When we do edge detection on an image now with currently available image processing techniques, we do it digitally, pixel by pixel. We scan an image and compare all of the neighboring pixels, and where there is a big difference between two, we label it an edge. With this computational metamaterial in the future, hopefully we will be able to do it all at once. The light from the image itself could go in and the edge-detected profile could come out the other side," explained Engheta.
The experts also looked into the possibility of having metamaterials in the future that will have adjustable properties where it will not be limited to just a single computation and allow for more manipulations. During the second part of the study, the proponents limited their simulations to involve materials such as aluminum-doped zinc oxide and silicon that fit current fabrication scenarios.
"...today we are able to control light propagation through a material in unprecedented ways, and realize material functionalities that would have been unthinkable only a few years ago. In this paper, we set the stage to have metamaterials realize a broad set of mathematical operations for us on-the-fly, as light propagates through them," said University of Texas at Austin associate professor Andrea Alu, one of the authors of the study.
It is all pure math for now but the next stage will be to test computational metamaterials for functions that will make more sense to humans.