Hospitals, power grids, aerospace systems, and science laboratories all carry highly sensitive technologies that allow the facilities to do what they need to do—as long as there are no strange and unwanted signals interfering. That’s easier said than done, but a team of engineers believe they may have the loudest solution ever: an invisible cloak.
In a recent Science Advances paper, researchers from the University of Leicester in the United Kingdom unveiled the idea of controlling the flow around an object so that it behaves as if “the object is not there,” according to the statement. Similar magnetic “coats” have been developed before, but the new concept is the first demonstration of a coat that works in any form of orientation.
“Magnetic cloaking is no longer a futuristic concept that is tied to perfect analytical conditions,” said Harold Luiz, senior research author and engineer at Leicester, in a statement. “This research shows that functional coatings, produced with complex geometries can be achieved, enabling next-generation solutions for protection in science, medicine and industry.”
Hiding from magnetism
As one of the four fundamental forces in nature, magnetism is everywhere on Earth. Many technologies—hard drives, MRIs, nuclear reactors—use magnetism to some degree, but unwanted magnetic fields can be a major nuisance, causing signal interference, data errors, or equipment malfunctions, the researchers explained.
Magnetic coats re-encode the magnetic field around the garment so that any external magnets that pass through cannot detect the object under the coat. Before this research, researchers had limited success when trying to make magnetic fabrics. And when they were able to make one, the coats were round or round, “reducing their practicality,” according to the paper.
Liquid invisible coat
The new concept, however, is surprisingly flexible. The researchers combined superconductors with soft ferromagnets to make the blanket. In this diagram, the superconductor element repels incoming magnetic fields, while the soft ferromagnets redirect the superconductors’ distortion of the magnetic lines into smooth states. This makes the external magnetic signal appear to be absent, the researchers say.
That said, this is a paper on the ideaand the team has yet to create a physical version of the coat. It should also be noted that the superconducting elements of the system only work under very cold temperatures, although the researchers say in the paper that “this should not undermine their performance, as the cryogenics industry that supports superconducting technology is already well established.”
“Our next step is the fabrication and testing of these magnetic coatings using high-temperature tapes and soft magnetic compounds,” added Ruiz. “We are already planning follow-up studies and collaborations to bring these projects to real-world settings.”
