After 1906, Ioffe worked in the Saint Petersburg (from 1924 Leningrad) Polytechnical Institute where he eventually became a professor. In 1911 he (independently of Millikan) determined the charge of an electron. In this experiment, the microparticles of zinc metal were irradiated with ultraviolet light to eject the electrons. The charged microparticles were then balanced in an electric field against gravity so that their charges could be determined (published in 1913).[2][3] In 1911 Ioffe converted from Judaism to Lutheranism and married a non-Jewish woman.[4] In 1913 he attained the title of Magister of Philosophy[5] and in 1915 Doctor of Physics. In 1918 he became head of Physics and Technology division in State Institute of Roentgenology and Radiology. This division became the Leningrad Physico-Technical Institute (LPTI) in 1917 and eventually the Ioffe Institute.
In the early 1930s, there was a critical need in the Air Defense Forces of the Red Army for means of detecting invading aircraft. A number of research institutes were involved with radiolokatory (radio-location) techniques. The Russian Academy of Sciences called a conference in January 1934 to assess this technology. Ioffe organized this conference, then published a journal report, disclosing to researchers throughout the world the science and technology that would ultimately be called radar.[6]
When the Soviet atomic bomb project began in 1942, Ioffe was asked to lead the technical effort, but refused the job on the grounds that he was too old. He saw great promise in the young Igor Kurchatov, and placed him in charge of the first nuclear laboratory. During Joseph Stalin's campaign against the so-called "rootless cosmopolitans" (Jews), in 1950 Ioffe was made redundant from his position of the Director of LPTI and from the board of directors. In 1952–1954 he headed the Laboratory of Semiconductors of Academy of Sciences of the USSR, which in 1954 was reorganized as the Institute of Semiconductors. Following Ioffe's death, in 1960 the LPTI was renamed the Ioffe Physico-Technical Institute and is one of Russia's leading research centers.[7]
^Mikerov, Alexander (2016), "From history of electrical engineering V: Electron discovery and its properties estimation", 2016 IEEE NW Russia Young Researchers in Electrical and Electronic Engineering Conference (EIConRusNW), St Petersburg, Russia: IEEE, pp. 3–7, doi:10.1109/EIConRusNW.2016.7448102, ISBN978-1-5090-0445-4, S2CID22681030
^Редакция. "Иоффе Абрам". Электронная еврейская энциклопедия ОРТ (in Russian). Retrieved 2024-10-07.
^Léon Theremin. "Termens Kindheit" (in German). Archived from the original on 2009-05-11. Retrieved 2009-02-25. Am 9. Mai 1913 fand die Verteidigung der Dissertation statt. ... Namens der Jury traten die Professoren Bergman und Chwolson auf, welche der Arbeit Joffes eine äußerst positive Bewertung ausstellten und meinten, dass sie vollauf des Magistergrades würdig sei.
^Ioffe, A. F.; "Contemporary problems of the development of the technology of air defense," Sbornik PVO, February 1934 (in Russian)
