The 100 Tesla Multi-shot

Vital Statistics Strength 90 tesla (100 tesla when completed) Type Pulsed magnet Bore size Insert: 15 mm (~0.59 inches) Outsert: 225 mm (~8.9 inches) Online since October 2006 Cost $10 million Stored energy (90 T) Outsert - 95 megajoules Insert - 0.8 megajoules Stored energy (100 T) Outsert - 120 megajoules Insert - 1.4 megajoules

Overview

This amazing magnet, located at the Mag Lab’s Pulsed Field Facility inside the Los Alamos National Laboratory in New Mexico, produces the highest non-destructive field in the world. The magnet is now operational at 90 tesla; a work in progress, its magnetic field will eventually reach 100 tesla. There are higher-field magnets out there; the problem is, they explode directly after the very brief experiments they are used for because they are not strong enough to withstand the forces created by such a powerful magnetic field.

This magnet is called a multi-shot because it can be used over and over again. In fact, researchers can pulse the magnet as frequently as once an hour.

The magnets at other Mag Lab facilities are superconducting, resistive or a combination of the two (the 45 tesla hybrid). The magnets at the Los Alamos facility are “pulsed” magnets. The fields they generate are so powerful they can be sustained only for a very short time. The field of this magnet lasts 15 milliseconds, allowing precise scientific measurements at the highest fields in the world. Although 15 milliseconds may not sound like much time, it is about two thousand times longer than what is otherwise available at this field intensity.

This magnet is powered by four separate electrical circuits. Three circuits comprise the large 100 tesla outsert magnet, which is powered by a 1.4 gigawatt generator. The insert circuit is powered by a 2 megajoule capacitor bank. The present peak field is 37 tesla for the outsert and 53 tesla for the insert. When the system reaches 100 tesla, the outsert magnet will generate 40 to 44 tesla and the insert will generate between 55 to 60 tesla.

This magnet is inside a liquid nitrogen container called a dewar, which keeps the magnet cool at about -198.15 degrees Celsius (-324.67 degrees Fahrenheit). This keeps the incredible discharge (“pulse”) of electricity that it receives from the power sources from overheating the magnet.

A 100 tesla magnet could have a profound impact on a wide range of scientific investigations, from studies of how materials behave under the influence of very high magnetic fields to research into the quantum behavior of phase transitions in solids. Researchers can explore extremes of low temperature and high magnetic field, which will contribute to our understanding of superconductivity, magnetic-field-induced phase transitions, and so-called quantum critical points, in which small changes in materials properties at very low temperature have dramatic effects on physical behavior. The magnet could also be used as a nanoscale microscope.

Links

For scientists:
• Users Hub: The Pulsed Field Facility
• First Experiments in the 100T Multi-Shot Magnet: Tuning Alloy Disorder in Diluted Magnetic Semiconductors (PowerPoint)

For the general public:
• Magnets from Mini to Mighty
• Commissioning of 100 Tesla Multi-Shot Pushes Boundaries of Science Beyond 80 Tesla (press release)