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Betsy Ancker-Johnson began a uniquely diverse and illustrious
career in physics, engineering and public service just after
World War II. Credited with a variety of inventions and achievements
including the development of a type of high-frequency signal
generator in the 1960s, she serves as one of the United States’
most distinguished role models for women as part of a generation
that helped to change perspectives on gender roles and aptitudes
in scientific fields.
Born on April 29,1927, Ancker-Johnson was inspired by her
mother, a homemaker, who encouraged her to wholeheartedly
pursue whatever was most interesting to her. She chose physics,
attending Wellesley College where she earned a bachelor’s
degree in 1949, then she moved to Germany to attend the University
of Tuebingen where she completed her Ph.D. in physics in 1953.
She married Hal Johnson in 1958 and the couple had four
children. Meanwhile she maintained a very active and fruitful
career that began first with a position at the University
of California, Berkeley, where she was a lecturer from 1953
to 1954; she moved on to the Inter-Varsity Christian Fellowship
in Chicago from 1954 to 1956; she then became a Senior Research
Physicist with the Microwave Physics Laboratory at Sylvania
Electric Products in Palo Alto, California from 1956 to 1958.
During these years she developed a specialization in plasma
and published a number of important research papers related
to the field.
Ancker-Johnson has described plasma as a fourth state of
matter after liquids, solids and gases. Among her observations
related to plasma studies were the occurrence of “pinching,”
as well as the phenomenon of microwave emission from an electron-hole
plasma — initiated only by the application of an external
electric field. Her work in this area lead to subsequent findings
that solid-state plasmas can serve as microwave sources of
During the 1960s, Ancker-Johnson worked for the David Sarnoff
Research Center at RCA, as well as for the Plasma Physics
Laboratory at the Boeing Science Research Laboratories in
Seattle, and then as an Affiliate Professor of Electrical
Engineering at the University of Washington from 1961 to 1973.
Also during this time, she served as visiting scientist at
Bell Laboratories, as well as supervisor in the division of
Solid State and Plasma Electronics at the Boeing Corporation.
It was while working with Boeing that she developed her
most famous invention — a type of signal generator based
on her finding that if a low-density plasma is established
in a piece of semiconductor material in the presence of a
high-intensity electric field and low-intensity parallel magnetic
field, very high frequency signals — well into the gigacycle
range — may be generated.
Ancker-Johnson found that if a plasma can be generated such
that the density of plasma varies from one portion of the
semi-conductor material to another, a relatively high intensity
electric field may be applied without the occurrence of impact
ionization. Normally, impact ionization phenomena prevent
the formation of low density plasma required for this invention
to work effectively. The necessary gradation in plasma density
can be created in numerous ways, including using semiconductor
materials with either a gradient in relative purities, surface
finishes, cross sectional area, or by applying appropriate
Ancker-Johnson was issued U.S. Patent #3,287,659 for “Signal
Generators Using Semiconductor Material in Magnetic and Electric
Fields” on Nov. 22, 1966. She has at least six other
patents in this area.
With this achievement behind her, in 1973, Ancker-Johnson
became the first female Presidential appointee in the U.S.
Department of Commerce when she took on the role of Assistant
Secretary for Science and Technology. She served until 1977
during the Nixon/Ford administration. From 1977 to 1979 she
served as Associate Laboratory Director, Physics Research,
at the Argonne National Laboratory in Argonne, Illinois. From
there she moved on to General Motors where she was named Vice
President of General Motors’ Environmental Activity
Staff in 1979. This marked the first time a woman was named
to the position of vice president in the U.S. auto industry.
Over the course of her career, Ancker-Johnson has written
more than seventy scientific papers and has received a variety
of honors and awards including membership in the American
Association for the Advancement of Science as well as the
Institute of Electrical and Electronic Engineers. In 1975,
she was the fourth woman elected to the National Academy of
Engineering (Lillian Gilbreth was the first, in 1965). She
retired from General Motors in 1992. As of 1988 she has served
as pro-bono Director of the World Environment Center.