Herbert Fröhlich (born 9.12.1905) is an English theoretical physicist and a Fellow of the Royal Society (1951). He was born in Rexingen (Germany). He graduated from the University of Munich (1930). In 1935 — 48 he worked at the University of Bristol, and in 1948 — 73 he was professor at the University of Liverpool.
His research concerned solid-state physics, superconductivity, field theory and meson physics. In 1937 he gave a complete theory of the stopping of electrons in ionic crystals (Fröhlich's theory of impact ionisation) and, together with F. Seitz, proposed a quantitative theory of the dependence of the breakdown field strength on thickness (Fröhlich's theory of breakdown). Independently of others he developed (1939) the theory of the scattering of electrons and holes by optical vibrations of the lattice. He constructed a theory of the mean free path of electrons in polar crystals. He was the first to investigate (1947) the influence of disorder on the spectrum of electronic states. He developed the theory of polarons (1950).
Independently of J. Bardeen he developed in 1950 a theory of superconductivity based on the consideration of electron-phonon interaction (the Fröhlich model), in which he predicted the isotope effect. In 1953 — 55 he gave a phenomenological theory of the excitation of plasma oscillations by electrons passing through a solid, in particular through a metal. Independently of others he constructed (1938) a vector meson theory of nuclear forces and predicted the existence of a neutral meson.
The M. Planck Medal (1972).