Igor Yevgenevich Tamm
Tamm, Igor Yevgenevich (1895-1971) was a Russian theoretical physicist who shared the 1958 Nobel Prize in physics with Ilya M. Frank and Pavel Alekseyevich Cherenkov for his work in explaining Cherenkov radiation.
Born in 1895 in Vladivostok, Russia, Tamm received a bachelor's degree in physics from Moscow State University in 1918. From 1922 to 1925. he taught at the J. M. Sverdlov Communist University in Moscow, and at Moscow State University from 1924 to 1937, where he was made head of the theoretical physics department in 1930. He earned his doctorate in 1933.
Tamm devoted much of his early research to the quantum theory of diffused light in solid bodies. He discovered that electrons bond in a certain way on the surface of a crystalline solid, giving that surface special properties. Known as “Tamm surface levels,” the discovery had a great impact on the development of solid-state devices, especially those with semiconductors.
In the mid-1930's, Tamm's colleague, Cherenkov, investigated the phenomenon that gamma radiation passing through a liquid medium produced a pale blue light. Cherenkov was able to determine several properties of the radiation, which is known as “Cherenkov radiation,” but he was unable to explain its origin.
Tamm and Frank theorized that objects cannot travel faster than the speed of light in a vacuum but can do so in other media. They proved mathematically that gamma rays passing through liquid emit electrons that form a wave that spreads out in advance of the gamma ray. In a liquid, when the wave velocity of the emitted electrons exceeds some given value, the blue glow results.
Tamm was director of the theoretical section of the P. N. Lebedev Physical Institute in Moscow from 1934 until his death in 1971. During that time, he did research on nuclear physics and elementary particles. He also examined plasma physics, which is critical to the development of controlled thermonuclear fusion reactions.