Abram Fedorovich Ioffe

Born Oct. 17 (29), 1880, in Romny, Poltava Province; died Oct. 14, 1960, in Leningrad. Soviet physicist. Academician of the Academy of Sciences of the USSR (1920; corresponding member, 1918); vice-president of the Academy of Sciences of the USSR (1926–29; 1942–45); Hero of Socialist Labor (1955). Member of the CPSU from 1942.

Ioffe graduated from the St. Petersburg Institute of Technology in 1902 and received the doctor of philosophy degree from the University of Munich in 1905. From 1903 to 1906 he worked as an assistant to W. K. Roentgen in Munich. Beginning in 1906 he was at the St. Petersburg (since 1924, Leningrad) Polytechnic Institute (from 1913 to 1948 as professor). In 1913 he was awarded the degree of master of physics; in 1915 he received the degree of doctor of physics for research on the elasticity and electrical properties of quartz. In 1918 he became head of the physiotechnical division, organized at his suggestion, of the State Roentgenologic and Radiological Institute in Petrograd, and subsequently, until 1951, he was director of the Physicotechnical Institute of the Academy of Sciences of the USSR created on the basis of that division. He was director of the Laboratory of Semiconductors from 1952 and the Institute of Semiconductors of the Academy of Sciences of the USSR from 1955. Beginning in 1932 he was director of the Physicoagronomic Institute, which was also organized on his initiative. Upon his initiative and with his participation, physicotechnical institutes were founded in Kharkov, Dnepropetrovsk, Sverdlovsk, and Tomsk.

In 1913, Ioffe proved the statistical nature of the emission of individual electrons in the photoemissive effect. Together with M. V. Kirpicheva, Ioffe was the first to explain the mechanism of electrical conductivity of ionic crystals (1916–23). With his colleagues Kirpicheva and M. A. Levitskaia in 1924 he obtained important results in the field of the strength and plasticity of crystals. It was shown that the strength of a solid increases by a factor of several hundred with the removal of microscopic surface defects; this discovery led to the development of high-strength materials (1942–47). The X-ray method of studying plastic deformation was developed during Ioffe’s investigations.

In 1931, Ioffe was the first to note the necessity for investigating semiconductors as new materials for electronics, and he undertook a comprehensive study of them. Methods for determining the basic quantities characterizing the properties of semiconductors were developed by him (with A. V. Ioffe). The study of the electrical properties of semiconductors carried out by Ioffe and his school (1931—40) led to the creation of a scientific classification for them. These works laid the foundation for the development of new fields of semiconductor technology—thermoelectric and photoelectric generators and thermoelectric cooling devices. In 1942, Ioffe was awarded a State Prize for his research in the field of semiconductors.

Ioffe’s most important contribution was the establishment of a school of physicists from which came many great Soviet scientists, including A. P. Aleksandrov, L. A. Artsimovich, P. L. Kapitsa, I. K. Kikoin, I. V. Kurchatov, P. I. Lukirskii, N. N. Semenov, and Ia. I. Frenkel’. Devoting much attention to pedagogical work, he organized a new type of physics department— the physicotechnical department—for the training of engineering physicists at the Polytechnic Institute in Petrograd (1918). He was awarded three Orders of Lenin. In 1961 he was posthumously awarded the Lenin Prize. Ioffe was an honorary member of many of the world’s academies of science and scientific societies.