In the wake of the successful detonation of the U.S 's first fusion device , codenamed '' Ivy Mike '' in 1952 , Stalin ordered Soviet scientists to build a comparable device , a program that was launched in 1953 . The directors of this project were Vitaly Ginzburg and Andrei Sakharov who originated this project as '' Sakharov 's Third Idea '' . Kurchatov contributed some of the calculations necessary for the Soviet Union 's first hydrogen bomb . Unlike Ginzburg , Sakharov , and Yakov Zel ' dovich , Kurchatov was only involved in small scale calculations , applying the basic nuclear weapons principles used in the smaller nuclear weapons that were developed under his directorship . In 1953 , the Soviet Union detonated its first thermonuclear device , codename '' Joe 4 '' . While other scientists , such as Ginzburg , Zel ' dovich and Sakharov earned renown , Kurchatov 's contribution was diminished
Ivy Mike
Ivy Mike
Igor Kurchatov