Levitated Dipole

A levitated dipole is a magnetic confinement approach to nuclear fusion that uses a superconducting ring magnetically levitated inside a reactor chamber, shaping its magnetic field into a dipole that mimics the structure of Earth own magnetosphere. Charged particles entering the field follow its curved lines and are reflected by the stronger field near the ring poles, while the region around the ring outer equator, comparable to Earth equatorial belt, confines the bulk of the plasma in a torus shape; plasma that drifts outward here meets rising field density and is pushed back rather than escaping, and plasma fluctuations tend to compress the plasma further rather than letting it dissipate. Physicist Akira Hasegawa proposed the concept as a fusion reactor design in 1987 after studying Voyager 2 encounter with Uranus magnetosphere, and in 1997 Jay Kesner of MIT and Michael Mauel of Columbia University proposed testing it, leading to MIT Levitated Dipole Experiment and Columbia Collisionless Terrella Experiment; more recently the private companies OpenStar Technologies of New Zealand, founded in 2021, and Deutelio of Switzerland, founded in 2022, have taken up the concept commercially.