Clinton Davisson

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Clinton Joseph Davisson
Davisson (left) with Lester Germer, 1927
Davisson (left) with Lester Germer, 1927
Born October 22, 1881(1881-10-22)
Bloomington, Illinois, USA
Died February 1, 1958 (aged 76)
Charlottesville, Virginia, USA
Nationality United States
Fields Physics
Institutions Princeton University
Carnegie Institute
Bell Labs
Alma mater University of Chicago
Princeton University
Doctoral advisor Owen Richardson
Known for Electron diffraction
Influenced Joseph A. Becker
William Shockley
Notable awards Comstock Prize (1928)
Elliott Cresson Medal (1931)
Nobel Prize in Physics (1937)

Clinton Joseph Davisson (22 October 18811 February 1958), was an American physicist who won the 1937 Nobel Prize in Physics for his discovery of electron diffraction. Davisson shared the Nobel Prize with George Paget Thomson, who independently discovered electron diffraction at about the same time as Davisson.

[edit] Life

Davisson was born in Bloomington, Illinois. He graduated from Bloomington High School in 1902, and entered the University of Chicago on scholarship. Upon the recommendation of Robert A. Millikan, in 1905 Davisson was hired by Princeton University as Instructor of Physics. He completed the requirements for his B.S. degree from Chicago in 1908, mainly by working in the summers. While teaching at Princeton, he did doctoral thesis research with Owen Richardson. He received his Ph.D. in physics from Princeton in 1911; in the same year he married Richardson's sister, Charlotte.[1][2]

Davisson was then appointed as an assistant professor at the Carnegie Institute of Technology. In 1917 he took a leave from the Carnegie Institute to do war-related research with the Engineering Department of the Western Electric Company (later Bell Telephone Laboratories). At the end of the war, Davisson accepted a permanent position at Western Electric after receiving assurances of his freedom there to do basic research. He had found that his teaching responsibilities at the Carnegie Institute largely precluded him from doing research.[1] Davisson remained at Western Electric (and Bell Telephone) until his formal retirement in 1946. He then accepted a research professor appointment at the University of Virginia that continued until his second retirement in 1954.[1]

Clinton and Charlotte Davisson had four children, including the American physicist Richard Davisson.

[edit] Electron Diffraction and the Davisson-Germer Experiment

Diffraction is a characteristic effect when a wave is incident upon an aperture or a grating, and is closely associated with the meaning of wave motion itself. In the 19th Century, diffraction was well-established for light and for ripples on the surfaces of fluids. In 1927, while working for Bell Labs, Davisson and Lester Germer performed an experiment showing that electrons were diffracted at the surface of a crystal of nickel. This celebrated Davisson-Germer experiment confirmed the de Broglie hypothesis that particles of matter have a wave-like nature, which is a central tenet of quantum mechanics. In particular, their observation of diffraction allowed the first measurement of a wavelength for electrons. The measured wavelength λ agreed well with de Broglie's equation λ = h / p, where h is Planck's constant and p is the electron's momentum.[3]

In honour of Davisson and his work, an impact crater on the moon, the Davisson Crater was named after him.

[edit] References

  1. ^ a b c Kelly, Mervin J. (1962). "Clinton Joseph Davisson," in Biographical Memoirs, Vol. XXXVI (Published for the National Academy of Sciences by Columbia University Press, New York, 1962), pp. 52-79.
  2. ^ Nobel Foundation (1937). Clinton Joseph Davisson: The Nobel Prize in Physics 1937. Les Prix Nobel. Retrieved on 2007-09-17.
  3. ^ Davisson, Clinton (1965). "The Discovery of Electron Waves", Nobel Lectures, Physics 1922-1941. Amsterdam: Elsevier Publishing Company. Retrieved on 2007-09-17.