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Tokamaks confine plasma magnetically.
Tokamaks and stellarators confine plasma at 150 million K with magnetic fields; inertial confinement compresses fuel with lasers. Net energy gain was achieved at NIF in 2022.
ITER aims for Q = 10.
Engineering challenges remain.
In more detail
Fusion reactors aim to confine hot plasma using magnetic fields, as in tokamaks, or inertial confinement using lasers. Producing net energy is the main challenge.
Real-world uses
- Research reactors such as ITER are testing plasma confinement.
- Inertial confinement experiments study fusion ignition.
- Fusion researchers use tokamaks, which use strong magnetic fields to hold hot plasma away from the walls.
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Frequently asked questions
Has net energy been produced?
Yes, in some inertial confinement experiments, but commercial power is still in development.
What fuel is used?
Deuterium and tritium, with lithium used to breed tritium.
What is a tokamak?
A doughnut-shaped magnetic confinement device in which a plasma is held by a combination of toroidal and poloidal fields.
Related topics in Atomic & Nuclear Physics
Nuclear weapons · Nuclear fusion · Fusion in stars · Neutron discovery · Neutrinos · Radiation detection