‘Antimagnet’ Renders Magnets Invisible

Posted by Heartmind Uncategorized Tuesday, March 27th, 2012

(Nature) Physicists have already unveiled invisibility cloaks that can hide objects from light, sound, seismic and even water waves. Now researchers report a cloak that can hide objects from static magnetic fields. This ‘antimagnet’ could have medical applications, but might also subvert airport security.

Writing in Science1, a team of theorists led by Alvaro Sanchez at the Autonomous University of Barcelona in Spain, together with experimentalists at the Slovak Academy of Sciences in Bratislava, describe a magnetic cloak made with inexpensive, readily available materials.

The cloak’s interior is lined with turns of tape made from a high-temperature superconductor. Superconductors repel magnetic fields, so any magnetic field enclosed within a superconductor would be undetectable from outside. But the superconductor itself would still perturb an external magnetic field, so the researchers coated its external side with an ordinary ferromagnet — the material that kitchen fridge magnets are made of. The superconductor tries to repel external field lines, whereas the ferromagnet tries to draw them in — together, the two layers cancel each other out.

Read the full article:
http://www.nature.com/news/antimagnet-renders-magnets-invisible-1.10292