Antimagnets: Controlling magnetic fields with superconductor-metamaterial hybrids

TL;DR

This paper introduces antimagnets, hybrid devices using superconductors and magnetic materials to conceal magnetic responses without disturbing external fields, enabling new applications in medical imaging and stealth technology.

Contribution

The paper presents a feasible design for antimagnets that conceal magnetic responses using readily available materials, unlike previous complex metamaterial-based approaches.

Findings

Antimagnets effectively hide magnetic responses without affecting external fields.

The design uses superconductors and isotropic magnetic materials, avoiding extreme material requirements.

Potential applications include MRI enhancement and magnetic stealth.

Abstract

Magnetism is very important in science and technology, from magnetic recording to energy generation to trapping cold atoms. Physicists have managed to master magnetism - to create and manipulate magnetic fields- almost at will. Surprisingly, there is at least one property which until now has been elusive: how to 'switch off' the magnetic interaction of a magnetic material with existing magnetic fields without modifying them. Here we introduce the antimagnet, a design to conceal the magnetic response of a given volume from its exterior, without altering the external magnetic fields, somehow analogous to the recent theoretical proposals for cloaking electromagnetic waves with metamaterials. However, different from these devices requiring extreme material properties, our device is feasible and needs only two kinds of available materials: superconductors and isotropic magnetic materials. Antimagnets may have applications in magnetic-based medical techniques such as MRI or in reducing the magnetic signature of vessels or planes.