In September 1951 , after a series of differences with Bradbury and other scientists , Teller resigned from Los Alamos , and returned to the University of Chicago . At about the same time , Ulam went on leave as a visiting professor at Harvard for a semester . Although Teller and Ulam submitted a joint report on their design and jointly applied for a patent on it , they soon became involved in a dispute over who deserved credit . After the war , Bethe returned to Cornell University , but he was deeply involved in the development of thermonuclear weapons as a consultant . In 1954 , he wrote an article on the history of the H-bomb , which presents his opinion that both men contributed very significantly to the breakthrough . This balanced view is shared by others who were involved , including Mark and Fermi , but Teller persistently attempted to downplay Ulam 's role . " After the H-bomb was made , " Bethe recalled , " reporters started to call Teller the father of the H-bomb . For the sake of history , I think it is more precise to say that Ulam is the father , because he provided the seed , and Teller is the mother , because he remained with the child . As for me , I guess I am the midwife . " With the basic fusion reactions confirmed , and with a feasible design in hand , there was nothing to prevent Los Alamos from testing a thermonuclear device . On 1 November 1952 , the first thermonuclear explosion occurred when Ivy Mike was detonated on Enewetak Atoll , within the US Pacific Proving Grounds . This device , which used liquid deuterium as its fusion fuel , was immense and utterly unusable as a weapon . Nevertheless , its success validated the Teller – Ulam design , and stimulated intensive development of practical weapons
Ivy Mike
Ivy Mike
Stanislaw Ulam