Kapitza, Peter Leonidovich (1894-1984)

Soviet physicist who shared the Nobel Prize for Physics in 1978 for his work on magnetism and low-temperature physics. He worked on the superfluidity of liquid helium and also achieved the first high-intensity magnetic fields.

Kapitza was born near St Petersburg and studied at Petrograd Polytechnical Institute, after which he went to the UK and worked at the Cavendish Laboratory, Cambridge, with nuclear physicist Ernest Rutherford. In 1930, Kapitza became director of the Mond Laboratory at Cambridge, which had been built for him. But when in 1934 he went to the USSR for a professional meeting, dictator Josef Stalin did not allow him to return. The Mond Laboratory was sold to the Soviet government at cost and transported to the Soviet Academy of Sciences for Kapitza's use. In 1946, he refused to work on the development of nuclear weapons and was put under house arrest until after Stalin's death in 1953. Kapitza was one of the first to study the unusual properties of helium II - the form of liquid helium that exists below 2.2 K (−271.0°C/−455.7°F). Helium II conducts heat far more rapidly than copper, which is the best conductor at ordinary temperatures, and Kapitza showed that this is because it has far less viscosity than any other liquid or gas. This property of helium is known as superfluidity. In 1939 Kapitza built apparatus for producing large quantities of liquid oxygen, used in steel production. He also invented a turbine for producing liquid air cheaply in large quantities.