London, Fritz Wolfgang

Fritz Wolfgang London, (born March 7, 1900, Breslau, Ger. [now Wrocław, Pol.]—died March 30, 1954, Durham, N.C., U.S.), German American physicist who did pioneering work in quantum chemistry and on macroscopic quantum phenomena of superconductivity and superfluidity.

London received his doctorate in philosophy (1921) from the University of Munich before switching in 1925 to study theoretical physics with Arnold Sommerfeld. He subsequently worked with Erwin Schrödinger at the University of Zürich and at the University of Berlin, where, as a Jew, he was dismissed from lecturing after the Nazis came to power in 1933. After several years at the University of Oxford in England and the Institut Henri Poincaré in Paris, he moved to the United States in 1939 to become a professor of chemistry (from 1949 also a joint appointment in physics) at Duke University, Durham, N.C. He became a U.S. citizen in 1945.

In 1927, together with the German Irish physicist Walter Heitler, London published the first quantum mechanical explanation of the molecular bond in hydrogen molecules and worked further to found chemistry upon quantum mechanics. (The London force is named after him. See van der Waals forces.) He then attacked the low-temperature phenomena of superconductivity and superfluidity, which he understood as macroscopic quantum effects. With his brother, Heinz London, he developed the first successful phenomenological theory (1935) of superconductivity, which crucially depends on the existence of an energy gap in electron states. London also suggested that Bose-Einstein condensation is responsible for superfluidity and predicted the quantization of magnetic flux.