"We have never succeeded In slowing down our nuclear fusion reactors."
Wilson Greatbatch, inventor
In 1950 Andrei Sakharov (1921-1989) took a break from designing nuclear weapons to study plasma physics with Igor Tamm (1895-1971) for a year, during which time they developed the concept for a machine that could produce energy through nuclear fusion. Tamm went on to win the 1958 Nobel Prize in Physics; Sakharov was awarded the 1975 Nobel Peace Prize. Progress on fusion power has been slow.
Nuclear fission produces energy by splitting highly radioactive atoms of uranium or plutonium. However, fission also produces waste that is dangerously radioactive for 10,000 years. Fusion, on the other hand, produces energy by combining deuterium (heavy hydrogen) into helium, with no dangerous waste. Sea water has one atom of deuterium for each 6,500 atoms of hydrogen. Deuterium atoms are twice as massive as hydrogen atoms, so they are relatively easy to separate. The energy thus promises to be inexpensive and clean.
Tamm and Sakharov's invention was called a TOKAMAK, the Russian acronym for a toroidal chamber with an axial magnetic field. The donut-shaped device uses magnetic fields to compress charged particles to the temperatures and densities required for fusion. In 1968,3 team led by Lev Artsimovich used a tokamak to produce the first terrestrial thermonuclear fusion reaction. It achieved a temperature of 8 million degrees Kelvin for 0.02 seconds.
