Heinrich Greinacher (May 31, 1880 in

St. Gallen , neighboring_municipalities = Eggersriet, Gaiserwald, Gossau, Herisau (AR), Mörschwil, Speicher (AR), Stein (AR), Teufen (AR), Untereggen, Wittenbach , twintowns = Liberec (Czech Republic) , website = ...

– April 17, 1974 in Bern) was a Swiss

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

. He is regarded as an original experimenter and is the developer of the

magnetron The cavity magnetron is a high-power vacuum tube used in early radar systems and currently in microwave ovens and linear particle accelerators. It generates microwaves using the interaction of a stream of electrons with a magnetic field while ...

and the Greinacher multiplier. Greinacher was the only child of master shoemaker Heinrich Greinacher and his wife Pauline, born Münzenmayer. He went to school in St. Gallen and studied

physics Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which r ...

at both Zurich,

Geneva , neighboring_municipalities= Carouge, Chêne-Bougeries, Cologny, Lancy, Grand-Saconnex, Pregny-Chambésy, Vernier, Veyrier , website = https://www.geneve.ch/ Geneva ( ; french: Genève ) frp, Genèva ; german: link=no, Genf ; it, Ginevr ...

and

Berlin Berlin ( , ) is the capital and List of cities in Germany by population, largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's List of cities in the European Union by population within ci ...

. He also trained as a

pianist A pianist ( , ) is an individual musician who plays the piano. Since most forms of Western music can make use of the piano, pianists have a wide repertoire and a wide variety of styles to choose from, among them traditional classical music, ja ...

at the Geneva Conservatory of Music. Originally a German citizen, he was naturalized in 1894 as a Swiss citizen. In Berlin, Greinacher attended the lectures of

Max Planck Max Karl Ernst Ludwig Planck (, ; 23 April 1858 – 4 October 1947) was a German theoretical physicist whose discovery of energy quanta won him the Nobel Prize in Physics in 1918. Planck made many substantial contributions to theoretical p ...

and received a doctorate in 1904 under

Emil Warburg Emil Gabriel Warburg (; 9 March 1846 – 28 July 1931) was a German physicist who during his career was professor of physics at the Universities of Strassburg, Freiburg and Berlin. He was president of the Deutsche Physikalische Gesellschaft 1899� ...

. He did his habilitation in 1907 at the

University of Zurich The University of Zürich (UZH, german: Universität Zürich) is a public research university located in the city of Zürich, Switzerland. It is the largest university in Switzerland, with its 28,000 enrolled students. It was founded in 1833 f ...

, and in 1912, he moved to Zurich on a permanent basis. From 1924 to 1952, he was full professor of Experimental Physics at the

University of Bern The University of Bern (german: Universität Bern, french: Université de Berne, la, Universitas Bernensis) is a university in the Swiss capital of Bern and was founded in 1834. It is regulated and financed by the Canton of Bern. It is a compreh ...

and the director of the Physical Institute (formerly Physics ''Cabinett''). In 1912, Greinacher developed the magnetron and gave a fundamental mathematical description of this tube. In 1914, he invented the Greinacher multiplier (a rectifier circuit for voltage doubling). In 1920, he generalized this idea to a cascaded

voltage multiplier 280px, Villard cascade voltage multiplier. A voltage multiplier is an electrical circuit that converts AC electrical power from a lower voltage to a higher DC voltage, typically using a network of capacitors and diodes. Voltage multipliers can ...

, and developed detection methods for charged particles (

proportional counter The proportional counter is a type of gaseous ionization detector device used to measure particles of ionizing radiation. The key feature is its ability to measure the energy of incident radiation, by producing a detector output pulse that is ''pro ...

, spark counter). In the 1930s, using an independently invented Greinacher-style multiplier to research atomic nuclei,

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies. ** Britishness, the British identity and common culture * British English, ...

researchers Cockroft and Walton discovered

artificial radioactivity Induced radioactivity, also called artificial radioactivity or man-made radioactivity, is the process of using radiation to make a previously stable material radioactive. The husband and wife team of Irène Joliot-Curie and Frédéric Joliot-Cur ...

. Greinacher was married twice: in 1910 to the

German German(s) may refer to: * Germany (of or related to) ** Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ge ...

Marie Mahlmann, with whom he had two children, and then again in 1933 to Frieda Urben from

Inkwil Inkwil is a municipality in the Oberaargau administrative district in the canton of Bern in Switzerland. History Inkwil is first mentioned in 1262 as ''Inchwile''. Geography Inkwil has an area, , of . Of this area, or 49.1% is used for agricu ...

Foundation

A foundation was established in Bern in 1988 with the name o
Heinrich-Greinacher-Stiftung
from the estate of the couple Frieda and Heinrich Greinacher. Interest income of the Foundation's capital is used to fund the Heinrich Greinacher Prize and for the promotion of young researchers and scientists.

References

*Heinz Balmer: Heinrich Greinacher zum Abschied. In: ''Physikalische Blätter''. Bd. 30 (1974), Heft 10, S. 463–465

Publications

*''Negotiations of the Swiss Society of Natural Sciences''. Issue 154 (1974), p. 239-251 (with a catalog) * Hans Erich Hollmann:''physics and technology of the ultra-waves. Volume 1 Production ultrakurzwelliger oscillations''.

External links

A video demonstration of a Greinacher tube
{{DEFAULTSORT:Greinacher, Heinrich 1880 births 1974 deaths Swiss physicists People from St. Gallen (city)

Foundation

See also

References

Publications

External links