Klaus Fuchs (1911 - 1988)

Klaus Fuchs was born on December 29, 1911, in Rüsselsheim, Germany. Born into a Lutheran family, Fuchs joined the Communist Party of Germany and fled to England following the rise of the Nazis in 1933. A brilliant young scientist, he earned his doctorate in Physics from the University of Bristol in 1937, and was invited to study at Edinburgh University.

At the outbreak of war, Fuchs, being a German citizen, was interned in a camp in Quebec, Canada. However, Professor Max Born of Edinburgh University intervened on his behalf, and by early 1941, Fuchs had returned to Edinburgh, where he was approached by Rudolf Peierls to work on the British atomic bomb research project. He became a British citizen in 1942.

In 1943, Fuchs was among the British scientists sent to the U.S. to collaborate on the atom bomb. At first, he was assigned to a team at Columbia University in New York. Later, he was transferred to the weapons laboratory in Los Alamos, New Mexico, where he worked in the theoretical division under Hans Bethe. His chief area of expertise was the problem of imploding the fissionable core of the plutonium bomb. He was present at the Trinity test.

Fuchs later testified that he passed detailed information on the project to the Soviet Union through a courier in 1945, and further information about the hydrogen bomb in 1946 and 1947. But it was not until 1948 that it was discovered that the Manhattan Project security had been breached, and not until 1949, when Fuchs had returned to England and the Harwell Atomic Energy Research Establishment, that he was confronted by intelligence officers as a result of the cracking of Soviet ciphers known as the VENONA project. Fuchs confessed in January 1950 and was convicted on March 1, 1950, and sentenced to 14 years in prison. His testimony to British and American intelligence agencies eventually led to the trials of David Greenglass and Julius and Ethel Rosenberg in the U.S.

The information Fuchs passed on the hydrogen bomb was too early to be of much material use since the key methods of making a hydrogen bomb work had not yet been discovered in the U.S. during the time Fuchs was working on the project (the Teller-Ulam mechanism was not discovered until 1951). On June 23, 1959, Fuchs was released and allowed to emigrate to Dresden, East Germany, where he resumed a scientific career. He died in East Berlin in on January 28, 1988.