May 14, 2005 would be the 90th anniversary of the birth of professor Anatoli
Robertovich Regel, the prominent Russian physicist, teacher, scientific
organizer, laureate of the State Prize, distinguished scientist, and laureate of
the A. F.Ioffe Prize of the Presidium of the Academy of Sciences. In the middle
of the last century, the Regel family immigrated from Switzerland at the
invitation of the inspector of gardens of the department of court. Eduard
Lyudvigovich Regel, the grandfather of Anatoli Robertovich Regel, became
director of the Botanical Imperial Garden in St.Petersburg1)
and a Russian nobleman. His younger son, Robert Eduardovich Regel', was
graduated from St. Petersburg University and the Fruit-Growing College in
Potsdam. After working in the same Botanical Garden and reading lectures at St.
Petersburg University and also in other cities in 1900, Robert Eduardovich Regel
started work at the Bureau of Applied Botany (known since 1916 as the Department
of Applied Botany). He became head of the Bureau in 1905 and was to devote his
entire life to it. As a result, applied botany won recognition and became a
required branch at all experimental and plant-selection institutions of Russia.
Here Robert Eduardovich Regel correctly saw a future leading scientist in the
student N.I.Vavilov, and promoted him to one of his deputies in 1917. After the
sudden death of Robert Eduardovich due to typhus in 1920, Vavilov became
director of the Department of Applied Botany. Under his directorship, the
Department was transformed into the All-Union Institute of Plant-Growing.
Anatoli Robertovich Regel developed an
interest in the natural sciences in his early years. In 1933 he became a
graduate student at the Physicomechanical Department, whose dean was A.F.Ioffe.
The thesis by A.R.Regel, "Plastification of amorphous objects," reporting work
carried out in the laboratory of A.P. Aleksandrov under the supervision of S.N.
Zhurkov, won high praise from the reviewer P.P.Kobeko. His brilliant defense of
his thesis and his diploma with distinction upon graduation from the Institute
won him the opportunity to start work at the Physicotechnical Institute of
Academy of Sciences of the USSR (1938), headed by Academician A.F.Ioffe.
In July of 1941, as part of a group of
the Physicotechnical Institute, Regel was sent to Sevastopol' to serve A.P.Aleksandrov, who was leading work on the demagnetization of ships of the Black
Sea Fleet. The need for this research arose because the German Navy was using
mines and torpedoes which sensed the magnetic fields of passing boats and ships.
In the opinion of Academician Aleksandrov, the contribution Regel made to the
solution of these problems in the demagnetization of ships of the Navy was
extremely important. The Navy command thought highly of the work of the
physicists. For this work, Regel was awarded the Order of the Red Star and the
For the Defense of Sevastopol' Medal. The organization of this work on
demagnetization was of course an emergency measure. This is one example of how
the Academy of Sciences not only found a theoretical solution to an important
problem which suddenly arose but also mobilized its members to do practical work
under difficult conditions to implement the solution, saving many human lives2
).
The Physicotechnical Institute of the Academy of Sciences continued to work
under evacuation conditions in the city of Kazan until May of 1945. In 1943,
Regel returned to his previous work, which had become a particular pressing
matter under wartime conditions. The results of the research on the behavior of
metals under dynamic loading were reported by Regel' as a dissertation offered
in his effort to win the scientific degree of Candidate of Physicomathematical
Sciences. The defense occurred in May of 1943 in Kazan. Two months after the
defense of this dissertation, Regel received the title and duties of a senior
scientific worker.
Research on semiconductors by Soviet and foreign physicists had by this time
generated a "critical mass" of experimental facts and had laid the
foundation for a theoretical understanding. Regel, however, managed to make
his own weighty contribution to this direction in solid state physics. After
defending his dissertation and completing a certain stage in his applied
work associated with armor, Regel' changed the thrust of his scientific
research slightly. His interest turned to the field of such fundamental
properties of crystals as strength, plasticity, viscosity, and the effects
of dislocations, point defects, etc., on the deformation of crystals. The
list of materials studied became longer. It now included not only metals,
but semiconductors also.
In 1945, just after the main collective of the Physicotechnical Institute
returned from evacuation, Ioffe suggested that Regel change fields and move
to the laboratory of V.P. Zhuze, where research on electronic semiconductors
was developing. In this new laboratory, Regel' studied semiconducting
compounds for several years (1945-1951) in parallel with work on isotope
separation which had begun earlier.
The laboratory of V.L.Kuprinenko, who was a student of Academician N.N.Andreev, formed at the Institute at this time. This laboratory was oriented
toward the development of physical foundations of the development of structural
armor. Regel' became the first worker in this laboratory. His scientific work
consisted of studying the behavior of materials at high deformation rates. The
results of this study provided Regel the basis for formulating an original
theory of the deformation of elastoviscous objects, which influenced thinking in
this field at the time. Even at this early state, Academician Ioffe predicted
that Regel would become a leading scientist. In May of 1945 he and some
colleagues returned to Leningrad and resumed work. The results of this important
research, by Regel' in collaboration with F.F. Vitman et al. have been published
in a special monograph3).
In the new laboratory he began to study electrical and other properties of
intermetallic compounds and semiconductors with the diamond and zinc blende
structures. As the subject of his first studies in this field, he selected
mercury monoselenide and mercury monotelluride, which crystallize in a zinc
blende structure. These choices were made on the basis of general considerations
developed at the Physicotechnical Institute by N.A.Goryunova. He succeeded in
showing that the mobility of charge carriers in these compounds reaches
record-high values. In 1951 his publication appeared4); some later,
industry began to manufacture Hall pickups for measuring magnetic fields which
were based on these and other semiconductors. Current converters,
magnetometers, frequency meters, and other devices were later developed on the
basis of these pickups. One reason why Ioffe and Regel forced developments in
this direction was an effort to seek ways to develop low-voltage devices for
converting the direct current from thermoelectric generators into alternating
current.
Regel had become interested in the possibilities of measuring magnetic fields
considerably earlier, during his work with the fleet. The effort to demagnetize
ships would have been unthinkable without simple, reliable, and sensitive
devices for measuring magnetic fields. At that time, Regel' had already taken
part in the design, fabrication, and comprehensive testing of a mechanical
magnetometer dubbed the "LFTI reel" (the letters LFTI being the Russian language
initials of the Leningrad Physicotechnical Institute). These devices served
reliably throughout the effort to demagnetize ships. Thirteen years later,
Regel' returned to this problem at a qualitatively new level (studying devices
for using the Hall effect to measure magnetic fields)5).
In 1950, at the Conference on the Properties of Semiconductors in Kiev, Regel and colleagues presented experimental proof, based on the example of indium
antimonide, of the validity of N.A.Goryunova's hypothesis that compounds of the
III-V group have semiconducting properties. Later on, compounds of this group
played an important role in the development of semiconductor electronics.
At approximately the same time, Regel and a few colleagues (A.I.Blum and
N.I.Mokrovskii) began a series of studies on the physical properties of molten
metals and semiconductors. This research would subsequently bring Regel'
widespread recognition and worldwide fame. His first publication on this topic
dates back to 1948 (Ref. 6). This field of physics became one of his primary
interests and remained so throughout his life.
Generalizing the results of research on a long list of materials with a variety
of crystal-chemistry characteristics, Ioffe hypothesized in 1947 that parameters
of a substance which characterize its semiconducting properties—the effective
mass of the charge carriers, the width of the band gap, etc.—are determined by
the short-range order, specifically by the nature of the chemical bonds of the
atoms of the substance, the coordination number, and the interatomic distances.
The long-range order, in contrast—the foundation of the band theory of
semiconductors—determines the conditions under which free carriers move in
solids and liquids. Regel' tested this hypothesis experimentally and confirmed
it in research on electrical properties of melts of various semiconductors. In
order to carry out this research, he developed a clever method for measuring the
electrical conductivity of molten materials without the use of electrodes—by
using rotating magnetic field. Two of these instruments were fabricated at the
Physicotechnical Institute, one for the Pedagogical Institute, and the other for
use at the Physicotechnical Institute for studying crystal-melt phase
transitions in materials with various structures. Careful planning of the
experiments, with work being carried out in parallel on the two instruments,
made it possible to extract some interesting physical results in a relatively
short time. It turned out that in those substances in which the short-range
order is destroyed upon melting the semiconducting properties of the crystals
transform upon melting into properties characteristic of metals. Among these
substances are germanium, silicon, and III-V compounds. If the short-range order
is instead preserved upon melting (as it is, for example, in the tellurides of
zinc and cadmium), then the semiconducting properties persist in the molten,
amorphous state. These results were of fundamental importance not only for solid
state theory but also for the effort to find new semiconductors in research on
glassy and amorphous substances.
The criterion which determines the role of short-range order in shaping the
electronic properties of a semiconductor has come to be known as the
"Ioffe-Regel criterion" 7,8). The paper entitled "Research on the
electronic conduction of liquids," which Regel' offered in seeking the
scientific degree of doctor of physical mathematical sciences in 1957, won him
this degree9). His defense at Leningrad State University was
brilliant. "His firm footing on liquids is as solid as though he were on dry
land," commented V.P.Zhuze after the defense.
The dissertation had been prepared a year earlier, in 1956; its text had been
submitted to Ioffe to read. However, Ioffe apparently forgot about the matter,
and about a year after receiving the text he asked Regel' about the status of
his defense. Learning that Regel' had done nothing, since he had not received
Ioffe's comments, Ioffe immediately wrote a glowing testimonial, which praised
the work highly: "The dissertation of A. R. Regel' is a monumental event in the
science of semiconductors and of the solid state in general. The author of this
dissertation has examined the entire wealth of new facts from a common
standpoint, taking account of both the nature of bonds and the positions of the
elements of the compounds in the periodic table... The novelty and
comprehensiveness of the results ... qualify this dissertation as an extremely
important contribution to the modern understanding of matter in its various
states."
Pursuing this research in later years, Regel had the opportunity not only to
formulate general laws regarding the electrical properties of substances as a
function of their composition, structure, and type of chemical bond at the
crossing of the melting point but also to study processes which occur at the
interface between liquid and solid phases, as well as phenomena in amorphous semiconducting films. Furthermore, the physical ideas developed by Regel in
this research have found applications in the fabrication of semiconductor
devices.
The work of Regel became well-known around the world, and Regel himself was
acknowledged as an authority in the physics of disordered systems. The founder
of the theory of the disordered state, N.Mott (Cambridge University), Laureate
of the Noble Prize, was always very interested in the studies of Regel' and
supported them. International conferences on amorphous and liquid semiconductors
have become regular events. The Sixth Conference was held in 1975 in Leningrad;
its organizing committee was chaired by Regel.
Regel remained interested in the disordered state for a long time. To some
degree or other, more than half of his (more than 200) scientific papers were
devoted to these topics. A list of his papers is published in the preprint
"Anatoli Robertovich Regel (1915-1989): Life and Scientific Activity
(excerpts)"21).
In 1968, while discussing the results of research on disordered systems and the
outlook for further research with his Moscow colleague and friend V.M. Glazov,
Regel suggested the joint preparation of a monograph on the physical properties
of electronic melts. The colossal work carried out by Regel and Glazov equipped
physicists with a three-volume encyclopedia of data and physical concepts on the
passage of a substance through its melting point10-12). For this
research on chemical thermodynamics of semiconductors, Regel was awarded the
State Prize in 1981.
In late 1950, Ioffe relinquished his post as director of the Physicotechnical
Institute, and in 1952 he became head of the independent Laboratory of
Physicomathematical Sciences, Academy of Sciences of the USSR. In 1954 this
Laboratory became the Institute of Semiconductors of the Academy of Sciences of
the USSR.
Regel followed his mentor without hesitation and became one of the people whose
shoulders bore the basic responsibilities of establishing the Laboratory. He
became part of the Scientific Council of the Laboratory and its scientific
secretary. From this time on he was perhaps the main assistant to the director
of the new laboratory, his support, and the person who carried out the
organizational work of Ioffe.
In 1955 Regel became deputy director of nonequilibrium processes in amplifiers
at the Institute of Semiconductors. Immediately after defending his doctoral
dissertation, even before confirmation at the Higher Certification Commission,
the Presidium of the Academy of Sciences confirmed Regel as deputy director of
the Institute of Semiconductors, at the initiative of Ioffe.
A while after his brilliant defense of his doctoral dissertation, some members
of the Scientific Council of the Institute suggested that all the most
interesting results seemed to have been found in the field to which Regel had
devoted more than five years of work—the problem of noncrystalline
semiconductors—and that he should move on to another topic, e.g., research on
phenomena in semiconductor diode structures, transferring his previous topic to
the colleges. Ioffe supported this idea. However, Regel did not share the
opinion that it was necessary to break off work in the prior field. Regel
retained warm spot in his heart for research on semiconductors in the disordered
state throughout his life. Problems of order and disorder associated with the
nature of the chemical binding in a substance, melts, amorphous solids, and
glassy materials always kept his interest. His scientific intuition did not let
him down. He pursued this research, regardless of just what his laboratory was
named at a given time and regardless of what sort of applied research he was
assigned by orders from above or was carrying out in fulfillment of contracts.
In his later years A.F.Ioffe became particularly closely involved in the
development of the Institute, writing a will, so to speak, specifying who would
replace him as director. In particular, he had previously prepared all the
necessary documents to appoint Regel's director of the Institute. Three years of
work as deputy director (1957-1960) served as a "probation period" for Regel
under the guidance of the many years of experience of the most prominent
organizer of physics in the country. This training was extremely useful for his
ten years as director. By this time the Institute of Semiconductors had emerged
as a prominent physics institute with definite fields of research in solid state
physics, with its own "personality", with a good creative collective, and with
bright prospects and authority in this country and abroad. The Institute was
called upon to be the major participant in several interesting physical and
important technical directions.
The thermoelectric conversion of thermal energy into electricity, a task
assigned to the A.F.Ioffe Institute, was one of the basic fields of work of the
Institute in those years. Having taken on some demanding administrative
responsibilities. Regel did everything possible to become the informal leader
in this research direction. The physics research on the broad class of
semiconductors; the development of highly effective thermoelectric materials,
namely chalcogenides of bismuth, antimony, and lead: thermoelectric cells and
batteres for generators and cooling devices for various temperature intervals,
including deep cooling; the development of specific thermoelectric apparatus—all
these directions benefited from an active participant, a scientific advisor, and
a consultant in the person of Regel.
He was directly involved in the transfer of the technology for preparing
materials for thermoelectric batteries to the Ust-Kamenogorski Metallurgical
Group of Enterprises. He helped pursue the development of a thermoelectric
generator for cathode protection of main gas and oil pipelines against corrosion
and the transfer of this work to a test factory of VNIIT near Moscow. As
president of the thermoelectric section of the Council on the Direct Conversion
of Energy, together with colleagues from the Institute of Semiconductors and the
Special Design Bureau, Regel actively collaborated in the development of a huge
technological base for the design and manufacture of large thermoelectric
generators at the Sukhumi Physicotechnical Institute and self-contained
generators working with thermal energy from radioactive decay at the Institute
of Radio Engineering in Moscow.
Ioffe and Regel put much emphasis on research on the defect structure of
crystals of semiconductors which were important for microelectronics. Regel'
became director of the laboratory of Diffusion and Defect Formation after the
death of professor B.I.Boltaks. He became immersed in the effort to solve these
problems. One of the last papers by Regel18) was on research on
structural conversions which occur in silicon single crystals as the crystals
are heated.
The broad physics background of Regel', his unprejudiced thinking, and the great
curiosity of this naturalist set the stage for work in "unexpected" directions
at the Institute of Semiconductors. As an example we might cite the effort
undertaken to study capillary phenomena in channels of monatomic dimensions
(1969-1971). Research on thermal conductivity became a good method for studying
The electron and phonon contributions, the defect structure of solids,
phonon-scattering mechanisms, and features of the band structure. Regel
participated directly in these studies along with colleagues, he published a
large review of research (this review is still the only one in the literature)
on the thermal conductivity of melts.
The foundation for the development of studies on the technical applications of
galvanomagnetic properties, in particular. Hall pickups, was research by Regel
and colleagues on semiconductors with a high carrier mobility. Small lots of
generators and converters of electrical signals, ammeters, and magnetometers
were developed and fabricated under laboratory conditions. In 1972 Regel headed
a large laboratory at the Physicotechnical Institute. Included in this
laboratory were sectors (later to become independent laboratories) of students
of Regel, which were organized at his initiative. He later directed the
laboratory of diffusion processes and defect formation as well as the laboratory
of low temperatures, preparing to relinquish his positions to one of his younger
colleagues.
From 1962 on Regel' was deputy president of the Scientific Council on the
Problem of the Physics and Chemistry of Semiconductors, headed by Academician B.M.Vul. chairman of the section of this Council on the physics of
semiconductors, and a member of the Scientific Council of the Academy of
Sciences of the USSR on the problem of the physicochemical foundations of
metallurgical processes. He participated in the work of the scientific councils
of the Physicotechnical Institute, the Institute of General and Inorganic
Chemistry, the Pedagogical Institute, etc.
His participation in, and coordination of, research on semiconductors reached
beyond the borders of our country. From 1973 on he was a member of the Soviet
delegation of the problems commission of the multilateral collaboration of
academies of sciences of countries of the Council of Mutual Economic Assistance
in accordance with the program of research on semiconductors. He regularly
participated in international conferences on the physics of semiconductors and
the physics of amorphous and liquid semiconductors.
Despite his colossal amount of activity in scientific and
scientific-organizational work in the Academy of Sciences, Regel always felt
obliged to carry out pedagogical work. He was not only a scientist by vocation
but also a born teacher. This gift was supported not only by his deep knowledge
of the subject but also by his careful, respectful relations with his audience,
even if it consisted of a single person in a conversation. The clarity and logic
of his thinking and arguments, his explicit formulation of problems, and his
ability to distinguish the most important of a mass of facts and to find and
describe the logical relationships among them always made a great impression on
his listeners. He began his pedagogical activity in the department of
theoretical physics of the Pedagogical Institute in 1947 at the invitation of
professor A.V.Stepanov. Preparation for the first lectures on courses on atomic
physics and quantum mechanics required much time and mental effort of him. He
complemented the reading of a general course in physics with interesting and
frequently original demonstration experiments, which fortified knowledge in new
branches of physics with an organization of laboratory studies of students. Many
students who carried out experimental course work under the supervision of
Regel later became his graduate students.
Regel stopped giving courses at the Pedagogical Institute only after he became
director of the Institute of Semiconductors. Even then, he did not break off
relationships with the educational institute. He actively cooperated in the
formulation of new work, including work on thermoelectric cells and batteries.
There were always a large number of graduate students in his laboratory at the
Institute of Semiconductors. Most of the graduate students in those years were
young scientists from the various republics of the USSR and from colleges and
specialists from industry. Regel' had graduate students from Armenia, Moldavia,
Kazakhstan, and Central Asia. About 30 candidate's dissertations were completed
under his supervision at the Institute of Semiconductors, and more than 70 at
the Pedagogical Institute21)
In 1986 Regel was awarded the title of Distinguished Scientist. Regel was
deeply in love with wildlife, gardens, and parks. He excelled in recongnizing
the calls of songbirds. In his student years he hiked in the Crimea, the Pamirs,
and the northern Urals. After the 1950s he became involved in kayak outings in
spring and summer. His wife Irina Alekseevna Il'inskaya and their son Aleksej
accompanied him on his summer outings. Living his last forty years on the
grounds of the Botanical Garden, he enjoyed its plants and collections daily
during the warm part of the year, and the hothouses the year-around, along with
his three children and six grandchildren. During trips abroad, he visited parks
as often as museums. In England, for example, he spent time in the Kew gardens
and hothouses. Regel loved paintings, music, and theater. He was very attentive
to and gracious with people.
Anatoli Robertovich Regel left us on December 27, 1989. We still have his
scientific works and our memories of the time we spent with him: with this a
thoroughly organized, intelligent person, eminent scientist, and teacher. For
those who worked alongside him, the living example of this kind and wise man
remains, consciously or subconsciously, an edification and a model to follow.
His grateful students, friends, and colleagues
Sov. Phys. Semiconductors 29 (5). May 1995
Compiled by A. G. Ostroumov.
Translated by D. Parsons
1. F.A. Brokgauz and I. A. Efron, Encyclopedic Dictionary [in Russian] (1891),
Vol. 4A. p. 8.
2. B.A. Tkachenko, History of the Demagnetization of Ships of the Soviet Navy
[in Russian] (Leningrad. 19X1).
3. A.F. Ioffe, F.F. Vitman, V.L. Kuprienkov, A.R. Regel' et al., Experimental
Data and Discussion of Structural Armor-Plating [in Russian] (Moscow, 1946).
4. A.I. Blum and A.R. Regel, Zh. Tekh. Fiz. 21, 316 (1951).
5. V.P. Zhuze and A.R. Regel, Technical Applications of the Hall Effect [in
Russian] (Leningrad, 1957).
6. A.R. Regel', Zh. Tekh. Fiz. 18, 1511 (1948).
7. A.F. Ioffe and A. R. Regel, Progr. Semicond. 4, 237 (1960).
8. "In memory of Anatoli Robertovich Regel' (1915 1989)," Fiz. Tekh.
Poluprovodn. 24, 954 (1990) [Sov. Phys. Semicond. 24, 601 (1990)].
9. A.R. Regel', Research on the Electronic Conductivity oj Liquids. Author's
Abstract, Doctoral Dissertation [in Russian] (Leningrad, 1957).
10. V. M. Glazov and A.R. Regel', The Periodic Law and Physical Properties
of Electronic Melts [in Russian] (Moscow, 1978).
11. V.M. Glazov and A.R. Regel'. Physical Properties of Electronic Melts [in
Russian] (Moscow, 1980).
12. V.M. Galazov and A.R. Regel', Formation of the Structure of Electronic
Melts [in Russian] (Moscow, 1982).
13. V.L. Gurevich and Yu.A. Firsov, Zh. Eksp. Teor. Fiz. 40, 198 (I960) [Sov.
Phys. JETP 13, 137 (1961)].
14. R.V. Parfen'ev, G.I. Kharus. I.M. Tsidil'koviskij, and S. S. Shalyt, Usp.
Fiz. Nauk 112, 1 (1974) [Sov. Phys. Usp. 17, 3 (1974)].
15. G.L. Bir and G.E. Pikus. Symmetry and Deformation Effects in Semiconductors
[in Russian]
((Moscow. 1972). 16Yu. A. Vodakov, Yu.S. Blank, and A.A. Mostovskii.
Fiz. Tverd. Tela (Leningrad) 5, 2228 (1963) [Sov. Phys. Solid State 5, 1621
(1963)].
17. Report of the A.F. Ioffe Physicotechnical Institute, Academy of Sciences of
the USSR, Leningrad (1972); state registration 72056354 (1977).
18. V. M. Glazov, V. B. Kol'tsov, V. Z. Kutsova, and A. R. Regel, Fiz. Tekh.
Poluprovodn. 25, 58 (1991) [Sov. Phys. Semicond. 25, 33 (1991)].
I9. F. G. Baksht, G. A. Dyuzhev. A. M. Martsinovskii, B. Ya. Moizhes, G. R.
Pikus, E. B. Sonin, and V. G. Yur'ev, Thermionic Conveners and Low-Temperature
Plasmas [in Russian] (Moscow. 1973).
20. A.R. Regel, I.A. Smirnov. and E.V. Schadrichev, Phys. Status Solidi(a) 15,
13 (1971).
21. G.A. Ivanov. Preprint A.F. Ioffe Physicotechnical Institute, Russian Academy
of Sciences. St. Petersburg, 1991.
