Remember the movie Harry Potter where people often missed Harry Potter under his invisibility cloak? Those amazing moments immediately created a desire for the fans to have one of their own. And you know that fiction inspires real sciences; there were some scientists among the fans who didn’t just dream of the cloak, they tried to create one. Some researchers from Queen Mary University of London (QMUL) have announced that they have successfully made a real progress towards this amazing cloak.
For the first time, the scientists made the demonstration of a practical cloaking device that makes curved surfaces appear flat to electromagnetic waves. They used a nanocomposite medium with seven distinct layers (called graded index nanocomposite) to coat a curved surface about the size of a tennis ball. Depending on their position the electric property of each layer varies, which, under certain frequencies, made the rounded shape appear flat. Albeit, in the past the method was able to cloak objects using only one frequency, the recent demonstrations showed the capability of the method to cloak objects in a bigger range of frequencies.
“The design is based upon transformation optics, a concept behind the idea of the invisibility cloak,” said project co-author Professor Yang Hao. So, the research may not lead to the invisibility cloak from the fiction, but the recent demonstrations show significant progress on the project. This design does have much wider applications, starting from microwave to optics to control any kind of electromagnetic surface waves.
“The study and manipulation of surface waves is the key to develop technological and industrial solutions in the design of real-life platforms, for different application fields,” said First author Dr. Luigi La Spada. “We demonstrated a practical possibility to use nanocomposites to control surface wave propagation through advanced additive manufacturing. Perhaps most importantly, the approach used can be applied to other physical phenomena that are described by wave equations, such as acoustics. For this reason, we believe that this work has a great industrial impact.”
An EPSRC programme grant – QUEST (The quest for ultimate electromagnetics using spatial transformations) funds the research and it is published in the journal Scientific Reports.