Nuclear fusion
A thermonuclear weapon is a type of nuclear bomb that releases energy through the combination of fission and fusion of the light atomic nuclei of deuterium and tritium. With this type of bomb, a thermonuclear detonation is triggered by the detonation of a fission type nuclear bomb contained within a material containing high concentrations of deuterium and tritium. Weapon yield is typically increased with a tamper that increases the duration and intensity of the reaction through inertial confinement and neutron reflection. Nuclear fusion bombs can have arbitrarily high yields making them hundreds or thousands of times more powerful than nuclear fission.