What is the Strongest Magnetic Coil?

The Record - Breaking “Little Big Coil 3”

As of now, one of the most remarkable achievements in this field is the “Little Big Coil 3” created by researchers at the National High Magnetic Field Laboratory (MagLab) at Florida State University. This coil has managed to generate a magnetic field of 45.5 tesla, breaking the previous record for the strongest continuous magnetic field. To put this into perspective, it's around 10 times stronger than a hospital MRI machine and a staggering 9000 times more powerful than a typical fridge magnet.

How It Works

Magnetism is a property of matter that is typically generated by moving electric charges. Scientists create strong magnetic fields by using coils of wire, often called solenoids. When an electric charge passes through these coils, a magnetic field is generated that travels through the coil. The key to increasing the magnetic field strength lies in increasing the density of the current passing through the coil.

“Little Big Coil 3” features a unique design. It has a superconducting magnet inside a resistive magnet. Instead of using the commonly used niobium - tin, it uses a tape coated with a kind of “cuprate” superconductor called rare - earth - barium - copper - oxide (REBCO). This superconductor can achieve superconductivity at higher temperatures. The tape is extremely thin, about the width of a hair, which allows it to be wound tightly. This tight winding increases the density of the electrical current, thereby enhancing the magnetic field strength. Another interesting aspect is that the team left off the insulation. Normally, insulation helps direct the current, but in this case, it could cause the superconductor to lose its superconducting properties, or quench. By leaving it off, the current density is increased, and it also allows for safer quenching, as reported in the research paper published in Nature.

Significance and Potential Applications

Intense magnetic fields like those generated by “Little Big Coil 3” are of great importance in basic science applications. They are crucial for understanding the properties of new materials. For instance, in material science research, these strong magnetic fields can be used to study how materials respond at the atomic and molecular levels, which may lead to the discovery of new materials with unique properties. Although the current experiment with “Little Big Coil 3” is a proof - of - concept, and it has only been able to sustain its magnetic field for a few seconds, it paves the way for the development of even more powerful magnets.