Juras Požela was born in Moscow on 5
December 1925. In 1926, his father, Karolis Požela, leader
of the Lithuanian Communist party was executed by firing
squad in Kaunas, Lithuania. His mother, Eugenija Tautkaitė,
was a writer. Until the start of the Second World War in the
USSR, Požela attended school in Moscow; in 1941 he entered
the School for Labour Reserve at V. Voitovich Rail
Rolling-Stock Maintenance Plant. After school, he began
working at the Vladimir Iljich Plant as a qualified turner.
In 1943, he volunteered for the army, and in 1944, as a
solder of the Soviet Army, he came to Lithuania. After the
war was over, Požela continued his studies at I.
Chernyakhovskiy Gymnasium in Vilnius. After graduating the
Gymnasium in 1946, Požela entered the Faculty of Physics and
Mathematics of Vilnius State University; from 1948 continued
to study at the Faculty of Physics of M.V. Lomonosov Moscow
State University, which he graduated with a diploma in
nuclear physics.
Požela became engaged in research activity in 1951, when
upon graduating the University, he started working as an
assistant at the Department of Experimental Physics of
Vilnius State University headed by Prof. P. Brazdžiūnas, the
initiator of semiconductor research in Lithuania. The
Professor encouraged Požela to change his specialization and
enter the postgraduate study course in Leningrad under the
supervision of academician A.F. Joffe. The area of research
of Požela as a postgraduate student was investigation of the
properties of semiconductors in strong electric fields.
Požela completed his postgraduate studies by submitting the
thesis “Some properties of semiconductors in strong electric
fields”, which he successfully defended at Leningrad State
University in 1956, and was granted the degree of Candidate
of Science in Physics and Mathematics. Požela subsequently
returned to Vilnius and started working as a junior
researcher at the Institute of Physics and Technology of the
Lithuanian Academy of Sciences. In 1956, the Institute of
Physics and Technology was reorganised, and on 1 October of
the same year, Požela became a senior researcher at the
Semiconductor Laboratory of the Institute of Physics and
Mathematics. While working at the Institute of Physics and
Mathematics, he continued investigating the transport
phenomena in semiconductors in strong electric fields, which
was a new direction of scientific research in Lithuania.
This area of research proved to be extremely prospective and
relevant. Consequently, a Section of Semiconductor
Electronics was established at the Institute in 1958, with
Požela as its head. Within a short period of time, he
managed to set up an experimental basis for semiconductor
research, he also proposed a new methodology for
investigating the properties of semiconductors by using
microwaves for free charge carrier heating, as well as
assembled a hard-working group of young and ambitious
researchers. Within a comparatively short period of time, a
sufficient amount of new research data was collected to form
a foundation for the doctoral thesis “The investigation of
charge carrier heating effect in semiconductors and its
application in radioelectronics”, which Požela successfully
defended in Leningrad in 1964, and was awarded the degree of
Doctor of Science in Physics and Mathematics (in 1993
nostrificated in Lithuania as Doctor Habilitatis of Natural
Sciences).
As Doctor of Physics and Mathematics, Požela embarked on the
study of plasma phenomena in semiconductors – a new
direction in scientific research. This research area was
closely related with the study of transport phenomena in
strong electromagnetic fields. The research paved the way
for a new direction in science – investigation of the plasma
of hot electrons in semiconductors. This also created all
the necessary prerequisites for the establishment of a new
institute of the Academy of Sciences. Thus, on the
initiative of Požela, and due to his sustained effort, the
Institute of Semiconductor Physics was opened on 1 January
1967. From the day of its foundation until 1990, the fast
growing Institute expanded its range of scientific activity,
with Požela acting as the initiator and leader in the
majority of the areas of new research. The most promising
areas appeared to be the investigation of electrogradient
effect, plasma and current instabilities in semiconductors.
While investigating the properties of semiconductors in
inhomogeneous electric fields, Požela and his colleagues S.
Ašmontas and K. Repšas discovered a hitherto unknown
phenomenon of the appearance of electromotive force and
electric conductivity asymmetry in a homogeneous
semiconductor, induced by asymmetrical inhomogeneous free
charge carrier heating in a strong electric field. This
scientific discovery was registered with the State Committee
for Inventions and Discoveries under the USSR Council of
Ministers in 1977. It was the first Lithuanian scientific
discovery entered into the Register of Discoveries.
Investigation of plasma and current instabilities in
semiconductors enabled Požela and his colleagues to
establish a whole range of new phenomena of significant
practical relevance. For the construction of the new
generation semiconductor devices – avalanche transit-time
diodes – as well as for the theoretic and experimental study
of the generation and amplification of microwave
oscillations academician Požela and a group of scientists
from Moscow were awarded the Lenin Premium in 1979. In 1988,
together with other researchers, Požela was granted the USSR
State Premium for the investigation of the physical basis
for the semiconductor devices controlled by magnetic field,
as well as the design and organisation of their industrial
production. Scientific achievement of Požela received high
recognition both in Lithuania – in 1968 he was elected
academician of the Lithuanian Academy of Sciences – and in
the Soviet Union – in 1984 he was elected Full Member of the
USSR Academy of Sciences. For his scientific and
organisational accomplishment Požela was awarded the Order
of the October Revolution and two Orders of the Red Banner
of Labour; in 1985 he was awarded the title of a Hero of
Socialist Labour; in 1995 – the P.L. Kapica Medal. J. Požela
is a Member of the European Academy (in London) and the
European Academy of Sciences and Arts (in Salzburg). Within
the latest years, Požela has reached significant achievement
in investigating the problems related with the designing of
ultrafast electronic devices; he also participated in the
CERN programme for the creation of ionizing radiation
detection devices. A group of scientists under his
supervisorship, together with researchers from Vilnius
University, participate in the programme for the development
of high-tech industries while focusing on the creation of
X-ray detection devices.
Academician Požela is an extremely creative and prolific
scientist. He has already written over 400 scientific
articles and 9 monographs, the most significant of which are
“Hot Electrons” (Vilnius, Mintis, 1971, in Russian), “Gunn
Effect” (Moscow, 1975, in Russian), “Plasma and Current
Instabilities in Semiconductors” (Moscow, Nauka, 1977, in
Russian; London, Pergamon, 1981, in English), “Physics of
High-Speed Transistors” (Vilnius, Mokslas, 1989, in Russian;
New York, Plenum, 1993, in English). The results of
scientific research are presented in a series of monographs
“Electrons in Semiconductors”, which in 1978 was launched by
the Publishing House Mokslas under the initiative and
editorship of Požela. Nine volumes of the series have
already been published and include description of the new
methods for calculating transport phenomena; the specifics
of magnetoplasma wave propagation in semiconductors and its
application in practice; theoretical basis of fluctuation
phenomena in semiconductors in nonequillibrium condition and
the possibilities for the use of those phenomena for the
diagnostics of solid state plasma; the properties of warm
and hot electrons and the methods of their investigation;
the new semiconductor transducers designed in the Institute
within the process of carrying out fundamental research of
the physical principles of their functioning, including the
description of their properties and construction basis.
Academician Požela devotes much effort to the implementation
of fundamental research into practice. He is the author of
over 100 inventions. The endeavour exerted by Požela to
facilitate industrial implementation of the outcome of
scientific research resulted in the establishment of an
experimental plant Helikonas under the Institute of
Semiconductor Physics in 1982. The plant produces in small
series semiconductor devices and equipment designed at the
laboratories of the Institute. In 1981, for the purpose of
promoting closer cooperation between research institutions
and industrial organisations, Požela initiated the
establishment of the Scientific–Industrial Complex
Electronika to coordinate the design of special
semiconductor instruments and new radioelectronic devices as
well as their production in Lithuania. The Complex included
the Institutes of the Academy of Sciences, universities,
industrial research organisations, and enterprises. For many
years, Požela was the head of this Complex.
Alongside with his extensive scientific activity, Požela
devotes much of his attention to the training of young
researchers. In the period between 1966 and 1976, Požela
taught the students of Vilnius University a course on the
subject of hot electrons and plasma phenomena in solid
state. In 1966, he was awarded the title of Professor.
Almost forty doctoral theses were submitted and successfully
defended under the guidance of Požela, ten of his doctoral
students have become habilitated doctors and professors.
Between 1976 and 1991, he was one of the heads of the
Specialised Board for the Defence of Doctoral Theses
assigned by the Supreme Attestation Commission under the
USSR Council of Ministers to Vilnius State University.
Academician Požela plays an equally significant role in the
organisation of scientific conferences and symposiums and in
the work of programme committees. In 1971, Požela launched
in Vilnius the first all-Union symposium “Plasma and
instabilities in semiconductors”, which has since been held
every three years and has gained global recognition. In
2004, already the twelfth International Symposium was held
in Vilnius, where academician Požela was invited to deliver
a report “Transport Phenomena in Two-dimensional Structures
with Quantum Dots”. He has also been included as member in
numerous programme committees of international conferences.
In addition to his comprehensive involvement in scientific
work, academician Požela also actively participates in
science organizational and public activities. In 1958 he was
appointed Deputy Director of Physics and Mathematics of the
Lithuanian Academy of Sciences, and in 1963 became Director
of this Institute; in 1967 he was appointed Director of the
newly established Institute of Semiconductor Physics of the
Lithuanian Academy of Sciences; in 1972 was elected
Vice-President of the Lithuanian Academy of Sciences, and in
the period from 1984 to 1992 – President of the Lithuanian
Academy of Sciences. Between 1992 and 1996, academician
Požela was a member of the Seimas of the Republic of
Lithuania. In this capacity, he devoted much effort to the
strengthening of the experimental basis of the Academy of
Sciences Institutes, took active interest in the training of
highly qualified researchers, as well as in the definition
of the principal trends in scientific research. Since the
first issue of the Lithuanian Physics Journal in 1961,
Požela has been a permanent member of its editorial board;
from 1967 – permanent member of the editorial board of the
journal “Semiconductors” (in Russian); from 1992 – President
of the Lithuanian Branch of the International Centre for
Scientific Culture – World Laboratory.
The organizational activity of academician Juras Požela has
received high acclaim in Lithuania. In 1965 he was bestowed
with the honorary title of Distinguished Scientist of
Lithuania. He was also granted the National Science Award of
Lithuania for the cycle of research work “Hot electrons and
their application in radioelectronics” (1965) and (together
with co-authors) for the works “Investigation of
electrogradient phenomena in semiconductors and their
application in practice” (1982). In 1995 he was awarded a
Third Class Order of the Lithuanian Grand Duke Gediminas,
and in 2000 Pope John Paul II honoured academician Požela
with his Commemorative Medal.
We have the honour to congratulate academician Juras Požela,
the most prominent physicist is Lithuania, on such a
distinguished anniversary and to wish him complete
fulfilment of his creative aspirations, success in
implementing new ideas and undertakings, and to be blessed
with unfailing health.
S. Ašmontas
J. Vaitkus
