Clarence Zener
Encyclopedia
Clarence Melvin Zener was the American
physicist
who first described the property concerning the breakdown of electrical insulators. These findings were later exploited by Bell Labs
in the development of the Zener diode
, which was duly named after him. Zener was a theoretical physicist with a background in mathematics who conducted research in a wide range of subjects including: superconductivity
, metallurgy
, ferromagnetism
, elasticity (physics)
, fracture mechanics
, diffusion
and, geometric programming.
Zener was born in Indianapolis, Indiana
and earned his PhD in physics under Edwin Kemble at Harvard
in 1929. His thesis was entitled Quantum Mechanics of the Formation of Certain Types of Diatomic Molecules. In 1957 he received the Bingham Medal
for his work in rheology
and in 1959 received the John Price Wetherill Medal from The Franklin Institute. A notable doctoral student of Zener's was John B. Goodenough
and Arthur S. Nowick held a postdoctoral appointment under Zener.
Zener was known both for his dislike of experimental work and for preferring to work on practical problems within the arena of applied physics, in which he was very insightful. Although he had a reputation of being very successful in these endeavors, he apparently considered himself as being less qualified to work on purely theoretical physics problems. In recognition of this, he once commented that after dining with physicist J. Robert Oppenheimer: "when it came to fundamental physics, it was clear there was no point in competing with a person like that."
He taught at Washington University in St. Louis (1935–1937), the City College of New York (1937–1940), and Washington State University (1940–1942) before working at the Watertown Arsenal
during World War II
. After the war, he taught at University of Chicago
(1945–1951) where he was Professor of Physics, before being appointed as Director of Science at Pittsburgh's Westinghouse (1951–1965). Here he developed his system of Geometric programming, which he used to solve engineering problems using adjustable parameters, defined by mathematical functions. Using this, Zener modelled designs for heat exchangers, to perform Ocean thermal energy conversion
, and discovered the most suitable areas for their deployment, many of these models are still being used today. Following his career at Westinghouse, Zener returned to teaching, leaving Pittsburgh to become a professor at Texas A&M University
(1966–1968), and finally at Carnegie Mellon University
(1968–1993).
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
who first described the property concerning the breakdown of electrical insulators. These findings were later exploited by 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...
in the development of the Zener diode
Zener diode
A Zener diode is a special kind of diode which allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage" or "Zener...
, which was duly named after him. Zener was a theoretical physicist with a background in mathematics who conducted research in a wide range of subjects including: superconductivity
Superconductivity
Superconductivity is a phenomenon of exactly zero electrical resistance occurring in certain materials below a characteristic temperature. It was discovered by Heike Kamerlingh Onnes on April 8, 1911 in Leiden. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum...
, metallurgy
Metallurgy
Metallurgy is a domain of materials science that studies the physical and chemical behavior of metallic elements, their intermetallic compounds, and their mixtures, which are called alloys. It is also the technology of metals: the way in which science is applied to their practical use...
, ferromagnetism
Ferromagnetism
Ferromagnetism is the basic mechanism by which certain materials form permanent magnets, or are attracted to magnets. In physics, several different types of magnetism are distinguished...
, elasticity (physics)
Elasticity (physics)
In physics, elasticity is the physical property of a material that returns to its original shape after the stress that made it deform or distort is removed. The relative amount of deformation is called the strain....
, fracture mechanics
Fracture mechanics
Fracture mechanics is the field of mechanics concerned with the study of the propagation of cracks in materials. It uses methods of analytical solid mechanics to calculate the driving force on a crack and those of experimental solid mechanics to characterize the material's resistance to fracture.In...
, diffusion
Diffusion
Molecular diffusion, often called simply diffusion, is the thermal motion of all particles at temperatures above absolute zero. The rate of this movement is a function of temperature, viscosity of the fluid and the size of the particles...
and, geometric programming.
Zener was born in Indianapolis, Indiana
Indianapolis, Indiana
Indianapolis is the capital of the U.S. state of Indiana, and the county seat of Marion County, Indiana. As of the 2010 United States Census, the city's population is 839,489. It is by far Indiana's largest city and, as of the 2010 U.S...
and earned his PhD in physics under Edwin Kemble at Harvard
Harvard University
Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...
in 1929. His thesis was entitled Quantum Mechanics of the Formation of Certain Types of Diatomic Molecules. In 1957 he received the Bingham Medal
Bingham Medal
The Bingham Medal is an annual award for outstanding contributions to the field of rheology. It was instituted in 1948 by the Society of Rheology, commemorating Eugene C. Bingham .-List of Award Winners:*1948 Melvin Mooney*1949 Henry Eyring...
for his work in rheology
Rheology
Rheology is the study of the flow of matter, primarily in the liquid state, but also as 'soft solids' or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an applied force....
and in 1959 received the John Price Wetherill Medal from The Franklin Institute. A notable doctoral student of Zener's was John B. Goodenough
John B. Goodenough
John Bannister Goodenough is an American professor and prominent solid-state physicist. He is currently a professor of mechanical engineering and materials science at the University of Texas at Austin...
and Arthur S. Nowick held a postdoctoral appointment under Zener.
Zener was known both for his dislike of experimental work and for preferring to work on practical problems within the arena of applied physics, in which he was very insightful. Although he had a reputation of being very successful in these endeavors, he apparently considered himself as being less qualified to work on purely theoretical physics problems. In recognition of this, he once commented that after dining with physicist J. Robert Oppenheimer: "when it came to fundamental physics, it was clear there was no point in competing with a person like that."
Career
Zener held the following posts/appointments:He taught at Washington University in St. Louis (1935–1937), the City College of New York (1937–1940), and Washington State University (1940–1942) before working at the Watertown Arsenal
Watertown Arsenal
The Watertown Arsenal was a major American arsenal located on the northern shore of the Charles River in Watertown, Massachusetts. Its site is now registered on the ASCE's List of Historic Civil Engineering Landmarks and on the U.S.'s National Register of Historic Places, and it is home to the...
during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. After the war, he taught at 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...
(1945–1951) where he was Professor of Physics, before being appointed as Director of Science at Pittsburgh's Westinghouse (1951–1965). Here he developed his system of Geometric programming, which he used to solve engineering problems using adjustable parameters, defined by mathematical functions. Using this, Zener modelled designs for heat exchangers, to perform Ocean thermal energy conversion
Ocean thermal energy conversion
Ocean Thermal Energy Conversion uses the difference between cooler deep and warmer shallow or surface ocean waters to run a heat engine and produce useful work, usually in the form of electricity....
, and discovered the most suitable areas for their deployment, many of these models are still being used today. Following his career at Westinghouse, Zener returned to teaching, leaving Pittsburgh to become a professor at Texas A&M University
Texas A&M University
Texas A&M University is a coeducational public research university located in College Station, Texas . It is the flagship institution of the Texas A&M University System. The sixth-largest university in the United States, A&M's enrollment for Fall 2011 was over 50,000 for the first time in school...
(1966–1968), and finally at Carnegie Mellon University
Carnegie Mellon University
Carnegie Mellon University is a private research university in Pittsburgh, Pennsylvania, United States....
(1968–1993).
Eponyms
- Zener diodeZener diodeA Zener diode is a special kind of diode which allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage" or "Zener...
- Zener pinningZener pinningZener pinning is the influence of a dispersion of fine particles on the movement of low- and high angle grain boundaries through a polycrystalline material. Small particles act to prevent the motion of such boundaries by exerting a pinning pressure which counteracts the driving force pushing the...
- Zener–Hollomon parameterZener–Hollomon parameterThe Zener-Hollomon parameter is used to help describe high temperature creep strain of a material such as steel....
- Landau–Zener formulaLandau–Zener formulaThe Landau–Zener formula is an analytic solution to the equations of motion governing the transition dynamics of a 2-level quantum mechanical system, with a time-dependent Hamiltonian varying such that the energy separation of the two states is a linear function of time...
- [Zener] Double-exchange mechanismDouble-exchange mechanismThe double-exchange mechanism is a type of a magnetic exchange that may arise between ions in different oxidation state. First proposed by Clarence Zener, this theory that predicts the relative ease with which an electron may be exchanged between two species, and has important implications for...
- Zener ratio, an elastic anisotropy factor for cubic crystals