The tokamak uses powerful external magnetic fields to confine and control the hot plasma of fusion fuels in a ring-shaped container called a ‘torus’.
It was first developed in the Soviet Union in the 1960s and was soon adopted by researchers around the world due to its enhanced performance compared with other approaches.
The Joint European Torus (JET – pictured), located at Culham Campus, is the largest and most powerful tokamak experiment currently operating. MAST Upgrade, also located at Culham, is a more compact and efficient type of device known as a ‘spherical tokamak’.
