Fusion reactors

thumb|A homemade fusor A fusor is a device that uses an electric field to heat ions to a temperature at which they undergo nuclear fusion. The machine induces a potential difference between two metal cages, inside a vacuum. Positive ions fall down this voltage drop, building up speed. If they collide in the center, they can fuse. This is one kind of an inertial electrostatic confinement device – a branch of fusion research.

HL-2M or HL-3 is a research tokamak at the Southwestern Institute of Physics in Chengdu, China. It was completed on November 26, 2019 and commissioned on December 4, 2020. HL-2M is now used for nuclear fusion research, in particular to study heat extraction from the plasma. With a major radius of , the tokamak is a medium-scale device. The magnetic field of up to is created by non-superconducting copper coils.