Robert Wichard Pohl (10.08.1884-5.06.1976) — German experimental physicist, member of the Göttingen Academy of Sciences. Born in Hamburg. Graduated from the Berlin institute (1906). In 1906—16 he worked at the Physical Institute of Berlin University; in 1916—52 —at the University of Göttingen (from 1919 — professor and director of the Physical Institute).
His work concerned solid-state physics, of which he was one of the founders, the physics of semiconductors, and the study of photoelectric phenomena and X-rays. He determined (1908) the wavelength of X-radiation, obtaining a value of 10-10 cm. In the 1920s he began a systematic study of the photosensitive properties of a number of semiconducting compounds and some insulating crystals and obtained the first systematic data on the photoconductivity of semiconductors, found a number of regularities of the internal photoelectric effect, and discovered the selective photoelectric effect. In particular, he studied the optical and electrical properties and the photoconductivity of single crystals of alkali halides, which at the same time served as model materials for investigating the processes of conduction in other crystals. In 1938 he showed that electron currents in a crystal can be controlled, giving in essence a description of the working principle of the semiconductor triode. He introduced the concept of the F-centre.
He was the author of the widely known three-volume “Introduction to Physics”, translated into many languages and issued in many editions: “Mechanics, Acoustics, the Theory of Heat” (17 editions), “Electricity” (20 editions), “Optics and Atomic Physics” (12 editions). He organised the so-called “Pohl Lectures” on experimental physics, which enjoyed great popularity.
He founded a school of physicists.
His work concerned solid-state physics, of which he was one of the founders, the physics of semiconductors, and the study of photoelectric phenomena and X-rays. He determined (1908) the wavelength of X-radiation, obtaining a value of 10-10 cm. In the 1920s he began a systematic study of the photosensitive properties of a number of semiconducting compounds and some insulating crystals and obtained the first systematic data on the photoconductivity of semiconductors, found a number of regularities of the internal photoelectric effect, and discovered the selective photoelectric effect. In particular, he studied the optical and electrical properties and the photoconductivity of single crystals of alkali halides, which at the same time served as model materials for investigating the processes of conduction in other crystals. In 1938 he showed that electron currents in a crystal can be controlled, giving in essence a description of the working principle of the semiconductor triode. He introduced the concept of the F-centre.
He was the author of the widely known three-volume “Introduction to Physics”, translated into many languages and issued in many editions: “Mechanics, Acoustics, the Theory of Heat” (17 editions), “Electricity” (20 editions), “Optics and Atomic Physics” (12 editions). He organised the so-called “Pohl Lectures” on experimental physics, which enjoyed great popularity.
He founded a school of physicists.