Clinton Davisson
Encyclopedia
Clinton Joseph Davisson 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.
. 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.
. 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. 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.
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 electron
s. The measured wavelength
agreed well with de Broglie's equation 
, where 
is Planck's constant and 
is the electron's momentum
.
. The crater Davisson
on the Moon is named after him.
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
who won the 1937 Nobel Prize in Physics
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
for his discovery of electron diffraction
Electron diffraction
Electron diffraction refers to the wave nature of electrons. However, from a technical or practical point of view, it may be regarded as a technique used to study matter by firing electrons at a sample and observing the resulting interference pattern...
. Davisson shared the Nobel Prize with George Paget Thomson
George Paget Thomson
Sir George Paget Thomson, FRS was an English physicist and Nobel laureate in physics recognised for his discovery with Clinton Davisson of the wave properties of the electron by electron diffraction.-Biography:...
, who independently discovered electron diffraction at about the same time as Davisson.
Early years
Davisson was born in Bloomington, IllinoisBloomington, Illinois
Bloomington is a city in McLean County, Illinois, United States and the county seat. It is adjacent to Normal, Illinois, and is the more populous of the two principal municipalities of the Bloomington-Normal metropolitan area...
. He graduated from Bloomington High School in 1902, and entered the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...
on scholarship. Upon the recommendation of Robert A. Millikan, in 1905 Davisson was hired by Princeton University
Princeton University
Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....
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.
Career
Davisson was then appointed as an assistant professor at the Carnegie Institute of TechnologyCarnegie Institute of Technology
The Carnegie Institute of Technology , is the name for Carnegie Mellon University’s College of Engineering. It was first called the Carnegie Technical Schools, or Carnegie Tech, when it was founded in 1900 by Andrew Carnegie who intended to build a “first class technical school” in Pittsburgh,...
. 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. 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
University of Virginia
The University of Virginia is a public research university located in Charlottesville, Virginia, United States, founded by Thomas Jefferson...
that continued until his second retirement in 1954.
Electron Diffraction and the Davisson-Germer Experiment
Diffraction
Diffraction
Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Italian scientist Francesco Maria Grimaldi coined the word "diffraction" and was the first to record accurate observations of the phenomenon in 1665...
is a characteristic effect when a wave is incident upon an aperture or a grating
Diffraction grating
In optics, a diffraction grating is an optical component with a periodic structure, which splits and diffracts light into several beams travelling in different directions. The directions of these beams depend on the spacing of the grating and the wavelength of the light so that the grating acts as...
, 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
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...
, Davisson and Lester Germer
Lester Germer
Lester Halbert Germer was an American physicist. With Clinton Davisson, he proved the wave-particle duality of matter in the Davisson–Germer experiment, which was important to the development of the electron microscope. These studies supported the theoretical work of De Broglie. He also studied...
performed an experiment showing that electrons were diffracted
Diffraction
Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Italian scientist Francesco Maria Grimaldi coined the word "diffraction" and was the first to record accurate observations of the phenomenon in 1665...
at the surface of a crystal of nickel. This celebrated Davisson-Germer experiment
Davisson-Germer experiment
The Davisson–Germer experiment was a physics experiment conducted by American physicists Clinton Davisson and Lester Germer in 1927, which confirmed the de Broglie hypothesis. This hypothesis advanced by Louis de Broglie in 1924 says that particles of matter such as electrons have wave like...
confirmed the de Broglie hypothesis that particles of matter have a wave-like nature, which is a central tenet of quantum mechanics
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...
. In particular, their observation of diffraction allowed the first measurement of a wavelength
Wavelength
In physics, the wavelength of a sinusoidal wave is the spatial period of the wave—the distance over which the wave's shape repeats.It is usually determined by considering the distance between consecutive corresponding points of the same phase, such as crests, troughs, or zero crossings, and is a...
for electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...
s. The measured wavelength
agreed well with de Broglie's equation , where is Planck's constant and is the electron's momentumMomentum
In classical mechanics, linear momentum or translational momentum is the product of the mass and velocity of an object...
.
Personal life
Clinton and Charlotte Davisson had four children, including the American physicist Richard DavissonRichard Davisson
Professor Richard Joseph "Dick" Davisson was an American physicist.Davisson was the son of Clinton Davisson, a Nobel laureate, and his wife Charlotte. His maternal uncle, Sir Owen Richardson, was also a Nobel laureate.During World War II he worked on the Manhattan Project as part of the Special...
. The crater Davisson
Davisson (crater)
Davisson is a lunar impact crater that is located on the far side of the Moon from the Earth. This crater lies across the eastern rim of the huge walled plain Leibnitz, and the rim and outer rampart intrudes into the interior floor of Leibnitz...
on the Moon is named after him.