Heinrich Welker

Heinrich Johann Welker (9 September 1912 in Ingolstadt – 25 December 1981 in Erlangen) was a German theoretical and applied physicist who invented the " transistron", a transistor made at Westinghouse independently of the first successful transistor made at Bell Laboratories. He did fundamental work in III-V compound semiconductors, and paved the way for microwave semiconductor elements and laser diodes.

Biography and important work

Starting in 1931, Welker studied at the University of Munich under Arnold Sommerfeld, and was granted a Ph.D. in 1936. The book '' Electrodynamics - Lectures on Theoretical Physics Volume III'' by Sommerfeld was based on lecture notes prepared by Welker during the winter semester of 1933/1934. Welker was granted his Habilitation under Sommerfeld in 1939.Mehra, Volume 6, Part 2, 2001, p. 868.

During the war years, 1940 to 1945, Welker worked at Luftfunkforschungs Institut in Oberpfaffenhofen, but still maintained association (1942 to 1944) with the physicochemical institute of Klaus Clusius at the University of Munich. After the war, 1947 – 1951, he took a job at the Westinghouse subsidiary in Paris, Compagnie des Freins et Signaux Westinghouse. From 1951 to 1961, Welker headed of the solid-state physics department of Siemens-Schuckertwerke, in Erlangen, where he developed the new, III-V compounds, to replace silicon semiconductors. His work resulted in large-scale use of galvanomagnetic and optoelectronic effects, as well as new switching circuits in microelectronics. Welker and his department paved the way for microwave semiconductors and laser diodes. He was the director of the Erlangen Siemens-Schuckertwerke research laboratory from 1961 to 1969. From 1969, until he retired in 1977, Welker was director of all the company's research laboratories.

While at the Westinghouse subsidiary in Paris, Welker and German physicist Herbert F. Mataré developed a point contact semiconductor amplifier, demonstrated in June 1948. This coincided with the announcement by Bell laboratory scientists of the demonstration of a point contact transistor on 30 June 1948. The French Westinghouse subsidiary applied for a patent on the same type of device on 13 August 1948. On 18 May 1949, this European invention coined as the "Le Transistron" or the "French transistor" was presented to the public, while a first batch of 1,000 devices was manufactured for the French telecommunications.Armand Van Dormael:''The "French" transistor.''Proceedings of the 2004 IEEE Conference on the History of Electronics, Bletchley Park, June 2004.
/ref> This development was an outgrowth of work done by the two independently in Germany in programs to develop German radar. The French patent was granted in 1952.

Welker was elected president of the Deutsche Physikalische Gesellschaft in 1977.

Siemens AG, Munich, in 1976 established the Heinrich Welker Memorial Award to honor Welker's pioneering work in III-V compound semiconductor development.Welker Award
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Heinrich Welker Memorial Award, Siemens AG. Award recipients are selected by the International Symposium on Compound Semiconductors Award Committee.

Selected Literature

* as cited i

*Arnold Sommerfeld and Heinrich Welker ''Über ein elektronentheoretisches Modell des Supraleiters. Mitteilung über die Arbeit.'', ''Sitzungsberichte der mathematisch-naturwissenschaftlichen Klasse der Bayerischen Akademie der Wissenschaften zu München'' page 5 (1938) as cited i

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Patents

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References

* Mehra, Jagdish and Helmut Rechenberg ''The Historical Development of Quantum Theory. Volume 6 The Completion of Quantum Mechanics 1926-1941. Part 2 The Conceptual Completion and the Extension of Quantum Mechanics 1932-1941. Epilogue: Aspects of the Further Development of Quantum Theory 1942-1999'' (Springer, 2001)
* Sommerfeld, Arnold, translated from the German by Edward G. Ramberg '' Electrodynamics - Lectures on Theoretical Physics Volume III'' (Academic Press, 1964)

Notes

{{DEFAULTSORT:Welker, Heinrich
1912 births
1981 deaths
Quantum physicists
20th-century German physicists
20th-century German inventors
People from Erlangen
People from Ingolstadt
Presidents of the German Physical Society