Uniformity: The Secret of Better Fusion Ignition

One of the ways to achieve thermonuclear fusion is through a controlled reaction between two light variants of hydrogen, called deuterium and tritium. Mauro Temporal, from the École Normale Supérieure Cachan, in France, and colleagues have made theoretical calculations indicating how best to improve the ignition stage of fusion reaction. Their approach, described in a paper published in The European Physical Journal D, involves increasing the uniformity of irradiation using high-power laser beams on the external shell of a spherical capsule containing a mix of deuterium and tritium.

Reaching uniformity of irradiation matters. Indeed, if it can be achieved, it rapidly heats up the capsule and makes it implode, compressing the fuel inside to very high density. This, in turn, induces the compression and heating of a small amount of fuel in a hot spot, which is a sine qua non for reaching the ignition conditions of thermonuclear fusion to produce large energy quantities.