Metamaterial magnetic wormhole moves magnetic fields

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Researchers have transferred a magnetic field across space with a length of special tubing that acted as if it were a hose that could carry magnetic fields without them losing strength. But external magnetic fields would be able to distort the fields inside the hose. To look like a wormhole, the tube itself had to be made invisible.

“We needed to make a 3D magnetic cloak to hide the magnetic hose,” Sanchez says. To do that, they used metamaterials – artificial materials that interact in unusual ways with electromagnetic fields and that may some day be deployed to build invisibility cloaks for light.

The team nested the hose inside a sphere of superconducting strips that deflect incoming fields (silver layer in figure above). But that deflection would be detectable, so they placed another sphere, this time of magnetic material, inside the strips to hide the superconductors (gold interior layer).

“We have a very fine-tuned concentration of attraction and repulsion,” Sanchez says. “The whole object is magnetically invisible because of this cancellation.”

(a) The field of a magnetic source (right) is appearing as an isolated magnetic monopole when passing through the magnetostatic wormhole; the whole spherical device is magnetically undetectable. (b) The wormhole is composed of (from left to right) an outer spherical ferromagnetic metasurface, a spherical superconducting layer, and an inner spirally wound ferromagnetic sheet

Abstract - Magnetic Wormhole

Wormholes are fascinating cosmological objects that can connect two distant regions of the universe. Because of their intriguing nature, constructing a wormhole in a lab seems a formidable task. A theoretical proposal by Greenleaf et al. presented a strategy to build a wormhole for electromagnetic waves. Based on metamaterials, it could allow electromagnetic wave propagation between two points in space through an invisible tunnel. However, an actual realization has not been possible until now. Here we construct and experimentally demonstrate a magnetostatic wormhole. Using magnetic metamaterials and metasurfaces, our wormhole transfers the magnetic field from one point in space to another through a path that is magnetically undetectable. We experimentally show that the magnetic field from a source at one end of the wormhole appears at the other end as an isolated magnetic monopolar field, creating the illusion of a magnetic field propagating through a tunnel outside the 3D space. Practical applications of the results can be envisaged, including medical techniques based on magnetism.

Scientific Reports - A Magnetic Wormhole

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Reposted via Next Big Future