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Why are deuterium and tritium used in many fusion reactor designs?
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fusion reactor
A tokamak is a device used in nuclear-fusion research for magnetic confinement of plasma.
Deuterium and tritium (D-T) are favored in fusion reactor designs primarily because they are the most efficient fuels for achieving controlled power generation.1
Several key factors make this reaction ideal:
- Lower Energy Requirements: Because both nuclei are hydrogen isotopes with a single unit of positive charge, they experience less Coulomb force (electrical repulsion) than heavier elements. This allows fusion to occur at more moderate, achievable plasma temperatures.12
- High Energy Yield: The D-T reaction provides a high energy output of 17.58 MeV per reaction.1
- High Cross Sections: The probability of these nuclei fusing, known as the cross section, is significantly higher than that of other potential fusion reactions.1
- Fuel Sustainability: While tritium does not occur naturally in large quantities, it can be bred within the reactor by capturing neutrons in a lithium blanket. This allows the reactor to effectively use deuterium and lithium as its primary fuel sources, both of which are abundant.2