The 1968–1969 verification of Soviet tokamak performance by a British team using laser diagnostics — the event that convinced the world to adopt the tokamak and abandon alternative concepts.
In 1968, Soviet scientists led by Lev Artsimovich reported that the T-3 tokamak at the Kurchatov Institute had achieved electron temperatures of ~1 keV and energy confinement times ten times better than any other device. The Western fusion community was sceptical — Soviet diagnostic techniques were considered unreliable, and the results seemed too good to be true.[1]
The confirmation triggered a worldwide “tokamak stampede.” Within five years, virtually every major fusion laboratory converted its existing experiments to tokamaks or began building new ones. Princeton converted its Model C stellarator to the ST tokamak. The UK built JET. France built Tore Supra. The tokamak became — and has remained — the dominant concept in magnetic confinement fusion.[2]
The 1968 tokamak confirmation is often cited as the most pivotal moment in fusion history. It concentrated resources on a single concept, accelerating progress but also reducing diversity. The recent revival of stellarators, mirrors, and alternative concepts represents a return to the pre-1968 plurality.[3]