Early years At the Siemens Research Laboratory II, Barwich became deputy to Hertz, who was director of the Laboratory. At that time, Hertz was a pioneer in
isotope separation.
In the Soviet Union Manfred von Ardenne, director of his private laboratory
Forschungslaboratoriums für Elektronenphysik,
Gustav Hertz, Nobel Laureate and director of Research Laboratory II at
Siemens,
Peter Adolf Thiessen, ordinarius professor at the
Humboldt University of Berlin and director of the
Kaiser-Wilhelm Institut für physikalische Chemie und Elektrochemie (KWIPC) in
Berlin-Dahlem, and
Max Volmer, ordinarius professor and director of the Physical Chemistry Institute at the
Berlin Technische Hochschule, had made a pact. The pact was a pledge that whoever first made contact with the Soviets would speak for the rest. The objectives of their pact were threefold: • Prevent plunder of their institutes, • Continue their work with minimal interruption, and • Protect themselves from prosecution for any political acts of the past. Before the end of
World War II, Thiessen, a member of the
Nationalsozialistische Deutsche Arbeiterpartei, had Communist contacts. On 27 April 1945, Thiessen arrived at von Ardenne's institute in an armored vehicle with a major of the Soviet Army, who was also a leading Soviet chemist. All four of the pact members were taken to the Soviet Union. Hertz was made head of Institute G, in Agudseri (Agudzery), about 10 km southeast of
Sukhumi and a suburb of Gul'rips (Gulrip'shi); Volmer was initially assigned to Hertz's institute. Topics assigned to Gustav Hertz's Institute G included: (1) Separation of isotopes by diffusion in a flow of inert gases, for which Gustav Hertz was the leader, (2) Development of a condensation pump, for which Justus Mühlenpfordt was the leader, and (3) Development of a theory of stability and control of a diffusion cascade, for which Barwich was the leader. Von Ardenne was made head of Institute A, in Sinop, Hertz, Barwich, and
Yuri A. Krutkov worked on uranium diffusion cascade control theory. Barwich also worked with V. S. Emel'ianov. In 1946, Barwich worked out the theory of natural stability of separation cascades. His results led to a reduction in the number of compressors required and the time needed for enrichment. In October 1948,
Gustav Hertz,
Peter Adolf Thiessen, and Barwich were sent to a classified location to advise on problems related to the startup of the gaseous diffusion plant D-1. Because of the milk drink
kefir they were served daily during their lengthy stay, they christened the place
Kieferstadt (
Kefirstadt); the location was Verkh-Nejvinskij, and it was known as
Sverdlovsk-44 within the Soviet atomic bomb project. In 1951, after the test of the first Soviet uranium atomic bomb, Hertz, Barwich, and Krutkov were awarded a
Stalin Prize, second degree, for their work on gaseous diffusion isotope separation. In preparation for release from the Soviet Union, it was standard practice to put personnel into quarantine for a few years if they worked on projects related to the Soviet atomic bomb project, as was the case for Barwich. Additionally, in 1954, the Deutsche Demokratische Republik (DDR, German Democratic Republic) and the Soviet Union prepared a list of scientists they wished to keep in the DDR, due to their having worked on projects related to the Soviet atomic bomb project; this list was known as the "A-list". On this A-list were the names of 18 scientists, dominated by members of the
Nikolaus Riehl group, which worked at Plant No. 12 in Elektrostal'. Barwich, not a member of Riehl's group, was on the list.
Return to Germany In April 1955, Barwich arrived in
East Germany. For a short time, he was an advisor to the German Academy of Sciences and an ordinarius professor for physics at
Halle University. In 1956, he became director of the
Zentralinstitut für Kernforschung (ZfK, Central Institute for Nuclear Research) and ordinarius professor at the Technische Hochschule Dresden. At the ZfK, Barwich's main objectives were to build and put into operation the first nuclear reactor of the German Democratic Republic (GDR), which was purchased from the Soviet Union, and to establish a research institute. The reactor went into operation in 1957. In 1959, the former Soviet spy
Klaus Fuchs was released from a British prison and was appointed Barwich's deputy at the ZfK. Barwich became a member of the atomic energy commission which reported to the Socialist Unity Party Central Committee, a member of the Council for the Peaceful Use of Atomic Energy, and a member of the GDR Research Council. His scientific contributions were recognized by the GDR's National Prize, second class. He was also appointed to the Council of Scholars of the
Joint Institute for Nuclear Research (Объединённый институт ядерных исследований, OIYaI) in
Dubna, Soviet Union. On 6 September 1964, just before the first Chinese atomic test, Barwich defected to the West, while at the Third Atoms for Peace Conference in
Geneva; he had met many of the Chinese atomic scientists while at Dubna. The same day, his wife went from
East Berlin to
West Berlin. While trying to defect his son Peter and his daughter Beate were arrested by GDR border police and after this sentenced to several years imprisonment. Later they were freed following a deal between GDR and West Germany. In December 1964, Barwich testified before the
United States Senate Subcommittee on Internal Security. Barwich died in
Cologne, aged 54. ==Personal==