I.
Cathode Rays and the Discovery of Electron
»
William Crookes, heir at an early
age to a large fortune, carried out his investigations in a private laboratory.
His studies of electrical discharges in gases, which followed the development
of the cathode ray tube by Pluecker and Hittorf, and his observations of
cathode rays and the dark space at the cathode led to the discovery of x-rays
and of the electron. Crookes also invented the radiometer, whose eventual
explication verified the kinetic theory of gases. Curiously, Crookes was a
believer in the occult and in the 1870’s claimed to have verified the
authenticity of psychic phenomena. Later he became involved in the Theosophical
Movement and there are references to his having exorcised demons. In 1897
Crookes was knighted by Queen Victoria (who is also reputed to have had an
interest in the occult) and in 1909 was elected president of the Royal Society.
»
Karl Ferdinand Braun (1850-1918)
was director of the Physical Institute and a professor of Physics at the
University of Strasbourg when he demonstrated the first cathode ray tube
oscillograph, guiding a narrow stream of electrons to a fluorescent screen and
presaging the modern television screen. Although little remembered today, Braun
made several important contributions. He discovered that rectification occurs
at a crystal/metal junction, leading to the introduction of crystal receivers.
In 1899, he introduced (sparkless) inductive coupling to antennas and the first
directive beam antenna. He received the Nobel Prize in 1909 along with
Guglielmo Marconi. Braun was in New York to testify in a patent suit when the
United States entered World War I; he was interned as an enemy alien and died
before the war ended
»
Wilhelm Conrad Roentgen (1845
-1923) was 44 years old, head of the Physical Institute and
recently retired Rector (President) of the University of Wurzburg when, in
November, 1895, he discovered that some unknown radiation coming from a Crookes
tube could cause crystals to fluoresce, pass through solid objects, and affect
photographic plates. Working alone, sometimes sleeping in his laboratory, and
maintaining great secrecy, he completed his research and eight weeks later
announced his discovery. The scientific and medical implications of his work
were immediately recognized and reported world-wide following its publication
on New Year’s Day in 1896. Within a few weeks some hospitals began to use x-rays.
Roentgen became one of the most renowned scientists in the world. He received
many honors, including the first Nobel prize in Physics and an offer (refused)
to be raised to the nobility.
»
J(oseph) J(ohn) Thomson (1856-1940),
the son of a Manchester bookseller, entered college at fourteen and at
twenty-eight was elected a fellow of the Royal Society and appointed to the
Chair of Physics at the Cavendish Laboratory. His great discovery occurred in
1897 during the course of his investigations of cathode rays. Thomson provided
convincing evidence that the rays consisted of charged particles; he measured
the ratio of charge to mass and was able to estimate that the mass was equal to
about 1/1800 of the mass of a hydrogen atom. His discovery of the electron won the
Nobel Prize in 1906 and he was knighted two years later. Thomson was described
by Rutherford as having "a most radiating smile, … when he is scoring off
anyone."
»
Robert A. Millikan (1868
-1953) began his career as a classics major at Oberlin College, but agreed
to teach Physics in order to earn more money. When he was offered a
fellowship in Physics at Columbia he accepted, but again only because it was
the best offer he could get financially. His academic career at the University
of Chicago was at first devoted to teaching and administration and he did not
begin to do research seriously until he was almost forty. Then, in 1906 he
began to devise a series of improvements to the Thomson experiment that led to
the oil-drop apparatus in which the charge of the electron was measured
conclusively. His results were published in 1910 and the last resistance to the
atomic theory of matter was dispelled. In 1914 he published the results of the
research for which he was awarded the Nobel Prize - the direct determination of
Plank’s constant using the photoelectric effect - verifying the 1905 Einstein
theory of the photoelectric effect and the quantum nature of light.
II.
Wireless Telegraphy
»
Heinrich Rudolf Hertz (1857-1894), a
professor of physics at Karlsruhe Polytechnic, was the first to broadcast
and receive radio waves in the laboratory. Between 1885 and 1889, he used spark
discharges to produce electromagnetic waves. Hertz's radiator consisted of a
pair of aligned rods, with a spark gap between them and capacitative plates at
their ends. His receiver was a loop of wire with a small gap across which a
small spark could be observed when the radiator discharged. Herz died suddenly
of a brain tumor when he was thirty six, perhaps never realizing that
transmission and reception over long distances was possible.
»
Edouard Eugène Désiré
Branly (1844-1940)
is revered in France as the inventor of wireless telegraphy. In 1890,
Branly, a professor of Physics at the Catholic University of Paris, discovered
that when exposed to even a distant spark transmission field, loose zinc and
silver filings would cohere and provide a path of increased conductivity that
could be used to detect the presence of the transmission. The
"coherer" took radio transmission out of the laboratory and made
communication over long distances possible.
»
Oliver Joseph Lodge (1851-1940)
held the chair in Physics at the University College in Liverpool when he
demonstrated a practical form of the Branly coherer in 1894. Lodge added a
device that shook the filings loose between spark receptions. It became a
standard device in early wireless telegraphy. Lodge also obtained the
first patents for the use of tuned circuits to adjust the frequency of
receivers and transmitters. After 1900, however, Lodge devoted himself to
psychic research and attempts to communicate with the dead. In 1902 he was
appointed the first principal of the new Birmingham University.
»
Guglielmo Marconi (1874-1937)
failed the entrance exams to the Italian Naval Academy and the University
of Bologna but was allowed by a family friend to attend lectures and laboratory
at the university. In 1896, at age twenty-two, he patented a successful system
of radio telegraphy . In the following years he introduced a notable series of
inventions and ingenious redesigns of transmitting and receiving system
components. In 1901 Marconi succeeded in receiving signals transmitted across
the Atlantic Ocean. It may be fairly said that Marconi single-handedly advanced
the development of radio telegraphy by decades. Marconi's Wireless Telegraphy
Company soon established a net of coast stations in Britain for ship-to-shore
communication. These were taken over by the British General Post Office in
1910, but for more than a decade the Marconi Company enjoyed a monopoly on
maritime radio equipment sales by virtue of an agreement with Lloyds of
London to only insure ships that used their equipment. In 1909 Marconi
received the Nobel Prize for Physics.
III.
Vacuum Tubes
»
Thomas Alva Edison (1847-1931)
was owner or co-owner of a record 1,093 patents. He also invented
the modern industrial research laboratory. In 1882, when one of his engineers,
William Hammer, observed the "Edison Effect" during the course
of experiments about the incandescent lamp, Edison, for reasons which he could
not later explain, uncharacteristically did not follow up on the
discovery. But, as he later admitted, at the time he did not even
understand Ohm's law. The Edison effect remained an unexplained curiosity
for fifteen years until the discovery of the electron.
»
John Ambrose Fleming (1849-1945)
had a remarkable career which spanned the first seventy-five years of the
development of electronics. Fleming was a student of Maxwell’s who later worked
as a consultant for Edison and then Marconi. In 1904, following Edison’s
observation of the passage of current from the filament to an anode in a light
bulb and J.J. Thomson’s discovery that cathode rays consisted of charged
particles, Fleming invented and patented the first electronic rectifier, the
diode, or Fleming Valve. The device was intended for use in
detecting the spark-generated radio waves of the time, replacing the other
devices used by the pioneers of radio communication. Fleming was knighted in
1929.
»
Lee De Forest(1873-1961), son of a
Congregational minister who was president of the Talledega College for Negroes
in Alabama, lived a long life full of controversy. He was defrauded by
partners, was involved in numerous patent suits, went through two divorces, and
once was indicted (but later acquitted) for mail fraud for seeking to sell a
worthless device (his audion tube), De Forest held more than 300 patents but is
most remembered for initiating the electronic revolution with his 1906
invention of the audion tube, a three-element vacuum tube in which the grid
controlled the current, which made modern radio possible. In 1912 he
conceived the idea of cascading triodes to achieve high amplification and also
independently discovered regenerative feedback.
»
William D. Coolidge (1873-1975), an
electrical engineering graduate of MIT and the University of Leipzig, joined
the General Electric Research Lab after a brief career in Academia. In
1911, he succeeded in fabricating a ductile form of tungsten which provided the
filaments for modern incandescent lamps and also patented a thoriated cathode
with improved emission for use in vacuum tubes. In 1913 Coolidge invented a
hot-tungsten filament x-ray tube which provided a more penetrating and reliable
source for radiology. The "Coolidge tube" became the standard
generator of medical x-rays.
»
Walter Schottky (1886-1976)
discovered the random noise due to the irregular arrival of electrons at the
anode of thermionic tubes that is called "shot noise" (Schottky
effect) in 1914 while studying under Planck in Berlin. Schottky was
Swiss, but he was educated and spent his professional career in Germany. In
1919 he invented the first multiple grid vacuum tube, the tetrode. Schottky
obtained multiple doctoral degrees, taught at universities from 1920 to 1927,
and then worked for Siemans for nearly five decades. He was the first to note
the existence of "holes" in the band structure of semiconductors,
discovered the type of lattice vacancy known as the Schottky defect, and in
1938 created a theory that explained rectification at a metal/semiconductor
interface.
»
Irving Langmuir (1881-1957),
son of a struggling Brooklyn businessman, showed a precocious interest in
Science. He received his degrees in Chemistry, but, tiring of the endless round
teaching elementary courses and paper grading required of professors, left
academia and went to the General Electric Research Laboratory. His work on
molecular films won the Nobel Prize in Chemistry in 1932, and his studies on
hot filaments in gases became the basis for improvements in incandescent
lighting and a huge industry. His discoveries about the emission of electrons
from cathodes and their behavior in vacuum tubes formed the basis for the
design of a variety of tube types.
IV.
Radio
»
Reginald Aubrey
Fessenden (1866-1932)
was a Canadian-American who first worked for Edison. In 1900, while working for
the U.S. Weather Bureau, he developed the ideas of continuouswave transmission
and amplitude modulation and the heterodyne principle to permit speech
transmission. After 1902, he directed the development of a one kilowatt, 50 kHz
alternator to replace the spark transmitter, and invented an electrolytic
detector for continuous waves. In December 1906 he realized the first
radio-telephonic broadcast. Fessenden held hundreds of radio patents and also
invented a variety of devices which included the radio compass and the
fathometer. He was described as "a stormy and colorful figure"
and for years he was deeply involved in a series of litigations against
his patents.
»
Edwin Howard
Armstrong (1890-1954)
was a junior engineering student at Columbia in 1912when he invented
regenerative feedback and electronic oscillators. Although a later corporate
suit brought by De Forest, led to the courts decision in favor of De Forest,
the engineering community has continued to regard Armstrong as the inventor.
Then in 1917 while serving in the army, Armstrong invented the superheterodyne
receiver which is the basis for virtually all modern radio and radar
communication systems. This patent was not disputed and Armstrong became a
millionaire. Armstrong’s third invention was the superregenerative detector.
Then, in 1933 Armstrong obtained a series of patents covering his invention of
(wideband) FM, a new system of radio communication. The radio industry, with a
vested interest in AM, had no interest in FM and Armstrong had to build the
first station himself. FM slowly gained acceptance, but Armstrong, impoverished
and embroiled in more patent suits, committed suicide.
»
Louis Alan Hazeltine (1886-1964)
became head of the Electrical Engineering Department at Stevens Institute of
Technology in 1917; this was the department which had awarded him his
bachelor’s degree only eleven years before. During World War I, he designed a
radio receiver for the U.S. Navy. In 1922, Hazeltine invented the
"neutrodyne" receiver to eliminate the squeaks and howls of the early
radio receivers. The Hazeltine amplifier neutralized the grid-to-plate
capacitative coupling which was a cause of oscillation in triode amplifiers. The
neutrodyne was the first commercial receiver suited to general public broadcast
reception. By 1927 some ten million of these receivers were being used by
listeners in the U.S.
»
Harold Stephen Black (1898-1983)
worked, after graduation from Worcester Polytechnic, for a department of
Western Electric Company which later became Bell Telephone Laboraotories.
For six years he pursued a seemingly futile project to improve the
distortion characteristics of amplifiers. In a storied incident, the
answer was conceived in a creative flash during a commuter ride on a ferry in
1927. He wrote the equations on a blank page in his daily newspaper.
Although at first it seemed paradoxical, negative feedback effected an
extraordinary performance in amplifier performance.
V.
Television
»
John Logie Baird (1888 -1946)
graduated from the University of Glasgow and worked for a while as an engineer
for a Glasgow electrical company, but was discharged when he blacked out half
the city in an unauthorized experiment to create diamonds. In the 1920’s Baird
began working on television using the Nipkow mechanical scanning disk. In 1926
he demonstrated the first television. He went on to demonstrate the first color
and stereo televisions and succeeded in recording his video signals on disks.
From 1929 to 1935, the BBC used the Baird mechanical television system; in the
last part of this period it shared time with the electronic
system. Mechanical systems, however, were limited to about 200 lines per
frame and could not compete successfully against electronic systems.
»
Philo Taylor
Farnsworth (1906-1971),
was a 15-year old Mormon high school student in Rigby, Idaho in 1922 when he
invented an electronic television system and explained it to his chemistry
teacher. In 1926, at age 19, he received some backing and formed a company to
develop television. By 1927 he had obtained his first patents, obtained
financing from a group of San Francisco bankers, and displayed the first
electronic television image. His success was announced in 1928, the first
public demonstration was given in 1934, and by 1936 his studio was broadcasting
to about fifty home receivers in Philadelphia. The next years were an
odyssey of litigation as RCA tried to break the Farnsworth patents which
blocked the kinescope and orthicon tubes. The Farnsworth patents were
repeatedly upheld and in 1939 RCA agreed to pay royalties to the Farnsworth
company.
»
Vladimir Kosma
Zworykin (1889-1982)
was educated in Russia and France and then saw service during World War I in
the Russian Army Signal Corps. After the war he emigrated to the United States
and worked initially for the Westinghouse Electric Corporation where in 1923 he
filed a patent application for the iconoscope, an electronic camera tube using
a photo-emissive array. However, it was not until 1929 that RCA offered him the
opportunity to continue working on television. Zworykin’s iconoscope led to
modern televison cameras and Zworykin's kinescope was the basis for the modern
television picture tube. His other inventions included a form of the electric
eye and his infrared image tube led to the sniperscope and the snooperscope. He
also invented a secondary-emission multiplier used in scintillation counters.
VI.
Radar
»
Robert Alexander Watson-Watt (1892-1973),
a descendant of James Watt, received a degree in Electrical Engineering from
the University of St. Andrews, Scotland and in 1915 began a career in the
British civil service, He patented his first radio location device, a device
for locating atmospheric discharges, in 1919. In 1935, he received his eleventh
radio-location patent, a device for detecting and locating an approaching
aircraft. In the following years he was the leader of the intensive development
of aircraft radio-location, the secret weapon of the Battle of Britain. In
1937, before the war began, Watson-Watt and his wife undertook the dangerous
task of traveling disguised as ordinary tourists through Germany, searching for
signs of German radar stations
»
Alfred Lee Loomis (1887-1975), a
graduate of Yale and Harvard Law School, was called "the last of the great
amateurs of science". Loomis made a fortune on Wall Street and used
his wealth to play host at his estate to famous physicists and to finance a
private electronics laboratory; he had already built a working low-power CW
radar for aircraft detection when the British brought the magnetron to the U.S.
in 1940. In the following months, Loomis helped found the Radiation
Laboratory and became head of the Microwave Committee of the National Defense
Research Committee. In 1940, Loomis conceived the idea of a precision
long-range radio navigation system, Loran. By 1942, the first Loran system,
operating at 1.95 MHz, was operating along the East Coast and was used to
direct surface vehicles the location of aircraft attacking submarines. Loomis
is also credited for conceiving the conical scan system for automatic radar
tracking of targets.
»
Isador Isaac
Rabi (1898-1988)
was brought to the United States at age three by his parents to escape the
poverty of Eastern Europe. His father labored in the sweatshops of New York
City and then opened a grocery store in Brooklyn to escape the tenements of
Manhattan. Rabi earned his degrees at Columbia and Cornell, and became a
professor of Physics at Columbia in 1937. In 1940, Rabi took leave from
Columbia to become director of research at the newly-formed MIT Radiation
Laboratory. Rabi, who hated the Nazis, would respond to any proposed project by
asking, "How many Germans will it kill?" The projects under his
immediate direction involved increasing the power and frequency of the
magnetron oscillators. In 1944 He was awarded the Nobel Prize for his (1937)
invention of the magnetic resonance method for determining atomic spectra.
»
Luis Walter Alvarez (1911-1988) was
one of the most versatile of the physicists who worked at the Radiation
Laboratory. Alvarez, who was of Irish-Spanish descent, was the son of a
prominent Mayo Clinic physician. He began his career as a nuclear physicist at
Berkeley in 1937 and made a number of fundamental discoveries. In 1940 he
joined the Radiation Laboratory staff and invented the Ground-Controlled
Approach radar for aircraft landing, a microwave early warning radar, and a
precision high-altitude bombing radar. In 1944 he transferred to the
Manhattan project, where he invented the implosion system for initiating atomic
explosions. He was awarded the Nobel prize in 1968 for his development of the
hydrogen bubble chamber and the discovery of many subatomic particles. In 1980,
he and his son, a geologist, co-authored the theory of the catastrophic
annihilation of the dinosaurs as the result of a massive meteorite impact.
»
Edward Mills Purcell (1912-1997)
grew up in a small Illinois town where his father managed the local office of
the telephone company. Purcell obtained a BSEE at Purdue and then turned to
Physics. He was an instructor at Harvard until he joined the newly formed
Radiation Laboratory where he led a group developing one centimeter wavelength
radar systems. It was discovered that these systems were limited by absorption
by atmospheric water vapor. This work put him on the track to his 1945
discovery of nuclear magnetic resonance in liquids and solids, the basis for
NMR medical imaging. In 1952 he was awarded the Nobel prize for this discovery.
»
Robert
Henry Dicke (1916-1997) delayed his arrival at the Radiation
Laboratory in order to finish his dissertation in Physics at the University of
Rochester. Dicke’s inventiveness led to 35 radar-related patents. He invented mono-pulse
and coherent-pulse radar and devices such as the magic-T waveguide junction. To
measure water vapor absorption at centimeter wavelengths, Dicke invented a
radiometer which became the standard detector for radio astronomy. Dicke later
became a professor at Princeton. He challenged Einstein’s general theory of
relativity and conducted a series of gravity experiments which were eventually
unsuccessful. He also correctly theorized that a microwave echo from the Big
Bang that created the universe could be detected.
VII.
Electrons and Waves
»
Ludwig Eduard
Boltzmann (1844
- 1906) was born and educated in Vienna, and held positions at Vienna, Graz,
Munich and Leipzig. Boltzmann’s work in statistical mechanics used the concepts
of probability to determine physical properties and contributed to the
development of quantum mechanics. His work was met with hostility by many
scientists: depressed and ill, Boltzmann committed suicide.
»
Max Karl Ernst Ludwig
Planck (1858-1947),
was one of the leaders of science in Germany until his retirement in 1928.
In 1900 he "guessed" the correct form for the blackbody radiation
function and attempted to justify the formula by assuming that radiation
consists of quanta of energy. Using the formula, Planck was able to deduce the
value of h, the Boltzmann constant k, Avogadro’s number
and the charge of the electron; he received the Nobel Prize in 1918. Plank,
whose career was marked by its devotion to the highest ideals, died broken by a
series of personal tragedies: his elder son was killed in World War I, his
daughters both died in childbirth in the next decade, and his second son was
implicated in the plot against Hitler and executed horribly by the Gestapo in
1945.
»
(Prince) Louis-Victor de
Broglie (1892-1987)
and his elder brother, members of the French nobility, broke with family
tradition and became physicists. His interest in conceptual problems in physics
led to a doctoral thesis which evoked the astonishment and skepticism of the
examining committee. He proposed that electrons had wave properties; this
duality of matter and waves offered an explanation of the restricted motion of
electrons around atomic nuclei. A copy of his thesis reached Einstein, whose
enthusiastic response led in turn to Schrödinger’s invention of wave mechanics.
»
Erwin Schrödinger (1887-1961) was an
Austrian Catholic who left Germany in 1933 in response to Nazi policies. After
the Nazi takeover, he and his wife then fled Austria with a single suitcase to
take refuge first in the Vatican and, later, in Ireland. Schrödinger’s theory
replaced the definite atomic particles of classical theory with an equation for
a wave function which is related to the probability of physical events. Oddly,
Schrödinger was unhappy with his own invention and spent great effort in
formulating objections to his theory. Schrödinger was a widely talented
individual who not only wrote popularizations of science, but also contributed
works on genetic structure, ancient Greek philosophy, and the history and
philosophy of science.
»
Enrico Fermi (1901-1954), was
the son of an Italian railroad employee. He received his doctorate from the
University of Pisa at age 21. In 1926 he developed the statistical method which
predicts the behavior of electrons and, shortly thereafter, was made a full
professor at the University of Rome at age 26. In 1938, he left Italy with his
family to receive the Nobel Prize and did not return; his known distaste for
the Fascist regime and the fact that his wife was Jewish had led to vicious
attacks in the rightist press. Fermi emigrated to the United States where, as
part of the Manhattan Project at the University of Chicago, he led the team
that achieved the first self-sustaining nuclear chain reaction
»
P.A.M. Dirac (1902-1984)
received a degree in Electrical Engineering from the University of Bristol,
England, but failing to find work, went on to graduate study in Physics. He
became one of the founders of quantum mechanics, predicted the existence of the
positron, developed the theory of the spinning electron and introduced the
quantum theory of radiation. He was awarded the Nobel Prize in 1933.
VIII.
Transistors
»
George Clarke
Southworth (!890-1972)
was born and raised in a small Pennsyvania town, received his bachelor’s and
master’s degrees from Grove City College and then went to Yale for his PhD. He
worked at the Bell Laboratories from its founding in 1934 until
retirement. His work on microwave waveguides in the early thirties stimulated
the development of radar. When he found that triodes would not function as
detectors at microwave frequencies, Southworth turned back to the use of the
crystal detectors of the early days of radio. His source for these was the
dusty bins of the second-hand, used radio shops of lower Manhattan.
»
Russell Shoemaker Ohl (1898-1987)
has been called the "forgotten man" in the invention of the
transistor. Ohl was trained in electrochemistry and graduated
fromPenn State in 1918. In 1927 he went to work for
the Bell Labs Holmdel facility. In 1940, during the course of
investigations of the properties of crystal detectors for radar, Ohl enlisted
the assistance of Bell chemists in preparing highly purified
silicon. They were able to produce ingots with n and p type silicon at
opposite ends of the same silicon melt. Ohl discovered the silicon
photodetector (and the first p-n junction device) when a section was
accidentally cut across an (invisible) boundary between p and n regions of a
silicon ingot solidifying from a doped melt. The device was shown to Brattain
who surmised that rectification was taking place at an internal surface
»
Karl Lark-Horovitz (1892-1958) was
an assistant professor at the University of Vienna who came
to the U.S. in 1926 via Canada, was naturalized in 1936, and
became a professor of Physics at Purdue. Lark-Horovitz built Physics
at Purdue into a major research department. In 1942, Lark-Horovitz and
his group began concentrating on the extraction of purified germanium crystals
for use as detectors for microwave radar; they also began doping the germanium
with other elements to determine how the rectification properties were
affected. In 1943 they succeeded in developing a very high back-voltage
unit that was mass-produced for use in radars. The Purdue physicists
openly described their results at technical meetings and
to Bell Laboratory personnel who came to Purdue. They were
unaware that the flow of information was
one-way; Bell Laboratory had made semiconductor research
company confidential. It is believed that Lark-Horovitz and his group were within
a few months of discovery of the transistor.
»
William Bradford
Shockley (1910-1989)
was born in London, but grew up in California and
was educated at Cal Tech and MIT. He joined the staff
of BellTelephone Laboratories in 1936. Beginning in 1939, Shockley began
to seek a way of converting a crystal rectifier into an amplifying device. The
war interrupted his work, but it was resumed in 1945 when Shockley returned
to Bell Labs as co-leader of the Solid State Physics
research group. The group included Bardeen and Brattain, who invented the
point-contact transistor. Shockley invented the junction transistor a few weeks
later. Shockley had a grating personality, and both Bardeen and Brattain
eventually left the group in irritation. In the 1970’s, Shockley aroused a
storm of criticism when he made public a theory of a genetic factor in
intelligence which implied an inferiority of blacks; in the 1980’s he aroused a
storm of scornful amusement when he announced that he had left frozen samples
of his (70-year old) semen for the artificial insemination of women of high
intelligence.
»
Walter H.
Brattain (1902-1987)
was born in China, the son of an American teaching school in Amoy,
and grew up on a ranch in Washington. He received his degrees
from Whitman College, the University of Oregon and
the University of Minnesota. In 1929 he went to work
for Bell Laboratories, investigating the behavior of copper-oxide
rectifiers until interrupted by the war, when he became involved in radar
silicon detector development. After, he returned to work in
the Solid StatePhysics group where he and Bardeen invented the point
contact transistor. Brittain was the experimentalist, Bardeen the theoretician,
but they worked closely together in the laboratory.
»
John Bardeen (1908-1991),
the son of the dean of the University of Wisconsin Medical
School, received a PhD in mathematical physics from Princeton, taught at
theUniversity of Minnesota, and was the principal physicist at
the Naval Ordnance Laboratory during World War II. After the war he was hired
by Bell Telephone Laboratories (at nearly twice his academic salary)
to work on theoretical problems of solid state physics. The breakthrough that
led to the invention of the point-contact transistor in 1948 came when Bardeen
developed a theory of the quantum surface states of electrons which led to the
conclusion that a charge layer existed at the free surface of semiconductors.
Bardeen left Bell Labs in 1951 to become a professor of electrical
engineering and physics at the University of Illinois. He shared
the 1956 Nobel prize with Shockley and Brattain for their joint invention of
the transistor. He also shared the 1972 Nobel prize with Cooper and Schrieffer
for the development of the theory of superconductivity, and thus became the
first to win two Nobel prizes in Physics.
SOURCE: http://www.ee.umd.edu/~taylor/Electrons.htm
SOURCE: http://www.ee.umd.edu/~taylor/Electrons.htm
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