Molecular Engineering: Fundamental Contributions
of Arthur von Hippel to Electroceramics
Markus Zahn
Massachusetts Institute of
Technology
Department of Electrical
Engineering and Computer Science
Laboratory for Electromagnetic and
Electronics Systems
Cambridge, MA 02139
1998 – A.R. von Hippel on occasion of 100th birthday
International Conference on Electroceramics
3-7 August 2003
[Presentation available at http://mit42v.mit.edu/lees/full/faculty/Zahn/zahn00.html]
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From the front and back covers of Life in Times of Turbulent
Transitions by Arthur R. von Hippel on the occasion of his
90th birthday, 1988.
Arthur von Hippel, 1986
Lichtenberg figure
– “art in science”
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Prof. Arthur R. von Hippel’s Career Summary
1898 - 1979
1898
1916-18
1924
1924-27
1927
1928
1929
1929-33
1930
1934
1935-36
1936
1939-64
Born in Rostock, Germany
Army buck private in field artillery and then lieutenant in World War I in France
Received Ph.D from Institute for Applied Electricity at the University of Göttingen with thesis
(summa cum laude) “The Theory and Investigation of the Thermophone”; allowed transmission of
radio broadcasts as free as possible of frequency distortions.
Assistant position to Prof. Max Wien, Physics Institute in Jena, Germany; studied sputtering of
metals and demonstrated that metal was released as atoms from the cathode by positive ion
bombardment.
Engaged to Marianne von Ritter; went alone to Berkeley, CA on a one-year Rockefeller
fellowship; measured the ionization characteristic of mercury atoms by electron impact.
Married Marianne von Ritter.
Marianne von Ritter died in flu epidemic
Privatdozent (Assistant Professor) at Second Physikalische Institute at University of Göttingen;
developed a basic understanding of electric breakdown in gases and single crystals and of the
meaning of Lichtenberg figures.
Married Dagmar Franck, daughter of James Franck.
Established Laboratory of Electrophysics at the University of Istanbul
Accepted invitation from Neils Bohr to be a guest professor at the Technical University of
Copenhagen
Joined MIT faculty as assistant professor of electrical engineering as “the physicist of the
Electrical Engineering Department.”
Founded MIT Laboratory for Insulation Research (LIR) ; researched Selenium rectifiers and photo
cells, radar dielectrics, ferroelectricity and ferromagnetism, electric breakdown, gas discharges,
solid-state physics.
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Prof. Arthur R. von Hippel’s Career Summary
1898 - 1979
1940
1942
1944
1947
1948
MIT Associate Professor of Electrical Engineering
Became naturalized American
Discovered ferroelectricity and piezoelectricity in barium titanate (BaTiO 3).
MIT Professor of Electrical Engineering
Received President’s Certificate of Merit, second highest civilian award in recognition of
“outstanding service to his country.”
1954-65
Wrote and edited books:
Dielectrics and Waves – 1954
Dielectric Materials and Applications – 1954
Molecular Science and Molecular Engineering – 1959
The Molecular Designing of Materials and Devices – 1965
1964-65
Scientific Advisor for the Office of Naval Research , Washington, DC and received the Superior
Civilian Service Award from the Department of the Navy.
1976
First recipient of Material Research Society’s von Hippel award, thereafter named for him, for his
interdisciplinary and pioneering research in dielectrics, semiconductors, ferromagnets, and
ferroelectrics; an international hallmark of excellence in the field of materials research.
1979
Last publication, “From Atoms Toward Living Systems,” Materials Research Bulletin, v.14, pp.273299; Last student, Keith W. Karvate, ScD in Electrical Engineering and Computer Science with thesis
“Electrical Surface Studies on Hexagonal Ice and Their Interpretation.”
Students and/or Colleague of:
Europe: Bohr, Sommerfeld, Heisenberg, Wien, Courant, Debye, Born, Franck, Hertz, Pauli
America: Loeb, Oppenheimer
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Early Years
Von Hippel family Coat of Arms
As World War I soldier on furlough (1918)
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Berkeley Year
With Marianne von Ritter before von Hippel left
for California on a Rockefeller fellowship at
Berkeley in 1927. They were engaged in 1927
and married upon his return in August, 1928.
Sadly, Marianne died from a flu epidemic in
early January, 1929.
In a $15 Chevrolet co-bought with a
Berkeley lab assistant in 1927.
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Von Hippel and his $15 Chevrolet after
their passage through Death Valley
von Hippel married Marianne on
August 14, 1928, shown here in front
of the Albani Church, Göttingen
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Return to Germany
Arthur and Dagmar von Hippel with their car
before Honer Weg #2 (1930)
Dagmar von Hippel (1930)
von Hippel received his PhD in 1924 from the University of Göttingen. He became friends with
James Franck, a professor at Göttingen. Franck and Hertz won the Nobel prize in 1926 for the
Franck-Hertz experiment which demonstrated that electrons colliding with mercury vapor atoms
lose kinetic energy in discrete quanta and that the excited mercury atoms re-emit that energy as
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discrete photons. von Hippel married Franck’s daughter, Dagmar, in the Summer of 1930.
Dagmar von Hippel with son Peter (1931)
Dagmar with Peter and Arndt on
their balcony in Turkey
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Von Hippel’s laboratory assistant in his
“white coat” when von Hippel established a
laboratory of Electrophysics in 1933.
Neils Bohr and James Franck, ~1935
von Hippel and family left Germany in 1933 because of Nazi anti-semitism as Dagmar
was Jewish. They spent one year at a new university in Istanbul, Turkey but the family
was not happy there. Then von Hippel accepted an invitation from Niels Bohr to be a
guest professor at the Technical University in Copenhagen in 1935-36. Father-in-law
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James Franck was then also a professor there.
Tisvilde: Arthur and James Franck playing
chess
Dagmar and Arthur going
swimming at Bohr’s summer
house in Tisvilde, Denmark
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Arthur relaxing (1948).
James Franck with his two grandchildren.
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James Franck and Albert Einstein on the occasion of their
receiving honorary degrees from Israel’s Technion University.
Neils Bohr and Isador Rabi look on. (Princeton, 1954)
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Lichtenberg Figures
Lichtenberg figures (G.C. Lichtenberg, 1777)
George Christoph Lichtenberg, Professor of Astronomy, Göttingen, 1742-1799
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+
Generation of a positive (above) or
negative (below) Lichtenberg figure
depending upon whether the electrons
are attracted toward or repelled from
the center electrode.
-
Diagram of the equipment and examples of
positive and negative discharges.
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Lightning over a city
Lightning striking a water column
created by an exploding mine.
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Lightning storm caused by the birth of
the volcanic island, Surtsey, off the south
coast of Iceland.
Lichtenberg figure more than a meter in
diameter burned by lightning into the grass
of a meadow.
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Escher’s “Thinker” (1898-1972). Dutch artist and friend of
von Hippel and the MIT Laboratory for Insulation Research.
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Electron clouds erupt from the electrode as show in this highly-magnified picture. Here a
heavy gas under pressure slows up the electrons as they fly out.
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Laboratory for Insulation Research (1940-64)
– pioneering in materials research, measurements, and instrumentation
Research Theme – molecular engineering for the “making of materials to order”;
molecular science and molecular engineering as a “broad new
discipline…comprising the structure, formation, and properties of atoms,
molecules, and ions; of gases, liquids, solids and their interfaces; the designing of
materials and properties on the basis of this molecular understanding; and their
imaginative application for devices.”
Studies – ferroelectrics and ferromagnetics; electric breakdown; dielectric
polarization; rectifiers and photo cells; gas discharges; solid-state physics
Education -
60 doctorate students, 2 electrical engineering degrees
47 master degree theses, large number of bachelor’s theses
Staff – In 1964 about 70 members in eight research groups. Seven of these groups
helped form the then new MIT Center for Materials Science and Engineering:
1. Crystal Physics (Prof. A. Smakula)
2. Magnetics (Prof. D.J. Epstein)
3. Magnetic Spectroscopy (Prof. P.A. Miles)
4. Structure Analysis (Prof. R.E. Newnham)
5. Photoconductor Systems (Prof. F. Chernow)
6. Mass Spectroscopy (Prof. C.K. Crawford)
7. Magnon-Phonon Spectroscopy (Prof. R.F. Morgenthaler)
As recognition, today the Center has a von Hippel conference room, Room 13-2127.
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This paper represents von Hippel’s career as it demonstrates the research quality practiced by L.I.R that justified its
worldwide reputation as a research center of excellence. The paper summarizes barium titanate research at L.I.R
since 1943, much of it being classified during World War II. In this paper von Hippel acted as a spokesman for his
physicist, chemist, electrical engineer, and ceramicist co-workers, and as such demonstrates the multidisciplinary
activities of L.I.R.
The paper is a “tour de force” in the von Hippel teaching tradition combining basic and applied research. The
rigorous and exhaustive fundamental physics and characterizing measurements of barium titanate ceramics are
described including: the Langevin function of dipole orientation; the locally acting electric field on a dipole leading
to the “Mosotti catastrophe”; plots of the dielectric constant, spontaneous polarization, specific heat and thermal
expansion, x-ray patterns, and piezoelectric coefficient versus temperature; diagrams of crystal structure; hysteresis
loops of barium titanate from -175ºC to +125ºC; field strength dependence of the dielectric constant; and
confirmation of the Curie-Weiss law. Realizing that a true understanding could only be obtained from single
crystal BaTiO3, he improved on the crystal growth procedure to produce beautiful crystal patterns viewable with
polarized light that depended on applied electric field or mechanical pressure. To describe the beauty of these
patterns he used the phrases “flickering of the transmitted colors resembled Broadway at night” and “patterns
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which rival in beauty Persian carpet designs.”
Fundamentals of Ferroelectrics
Langevin function
Barium titante crystal structure
Ideal pervskite structure.
Field response of perfect dipole gas, described by Langevin function
.
Ferromagnetic and ferroelectric
hysteresis loops
Ferroelectric hysteresis loops
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Applications of Ferroelectric Ceramics
Dielectric Amplifiers
Dielectric amplifier
operated near resonance.
Simple one-element saturable condenser.
Crystal Resonators
Bridge-connected saturable condensers.
Dielectric Amplifiers
Use of prepolarized ferroelectric ceramics as
torsional vibrators.
Equivalent circuit and frequency response
near resonance of a piezoelectric crystal.
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Ferroelectric Transducers
Langevin’s quartz hydrophone
BaTiO3 transducer operating against a clamped load.
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Barium titanate transducer driving a metal horn.
Measured Values of Dielectric Constant and Loss Tangent in
Ceramics as a Function of Frequency
[Dielectric Materials and Applications, A.R. von Hippel, Editor, 1954]
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Temperature Dependence of Barium Titanate Properties 1
Temperature dependence of Young’s modulus (a) and of dielectric and piezoelectric constant (b) of various barium
titanate ceramics.
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Temperature Dependence of Barium Titanate Properties 2
Ferroelectric hysteresis loops.
Dielectric constant of barium titanate ceramic as
function of temperature. (Measurements of W.B.
Westphal, Laboratory for Insulation Research.)
[ 
Variation of all dimension of barium
titanate with temperature. (After Megaw.)
3Tc
N2
, Tc 
]
T  Tc
9 0 k
Confirmation of Curie-Weiss law on bariumstrontium titanate ceramic. (After Roberts.)
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Infrared Vibrations of BaTiO3 and Fe3O4.
(Measured by Last and Waldron.)
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Fundamental Properties of Barium Titanate
Field-strength dependence of dielectric
constant for barium-strontium titanate ceramic
(above Curie point). (After Roberts.)
Temperature dependence of dielectric constant and
loss tangent of barium titanate ceramic. (Measurements
of W.B. Westphal, Laboratory for Insulation Research.)
Resonance spectrum of BaTiO3 disk. (After Roberts.)
Relaxation spectrum of the ferroelectric state in
barium titanate ceramic at room temperature.
(Measurements of W.B. Westphal, Laboratory for Insulation
Research.)
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Dielectric Constant and Phase Transitions of BaTiO3.
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Typical Physical Properties of Ceramic Dielectrics
Vitrified Products
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Hysteresis Loops of Barium Titanate Ceramics.
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Hysteresis Loops of Single Domain Barium Titanate
Crystals Before and After the Forming Treatments of
Several Heating Cycles With Systematically Increased
Field Strength.
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Barium Titanate Memory
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X-ray Patterns of Barium Titanate ceramics.
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Domain Areas in BaTiO3 Crystal and Effect of Electric Field.
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BaTiO3 Crystal Viewed in Polarized Light
Parallel to Strong Field.
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Wedge-shaped Laminar Domains in BaTiO3 Single Crystal.
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Square Net Domain Pattern of BaTiO3 Single Crystal.
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M. Zahn Research in
Surfactant Stabilized
Ferromagnetic Colloidal
Suspensions of Magnetic
Nanoparticles (Ferrofluids).
Ferrohydrodynamic
Instabilities in DC Magnetic
Fields
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Ferrofluid
Drops in
Rotating
Magnetic
Fields
Ferrohydrodynamic
Drops
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