Stefan Janos (Physicist)
Encyclopedia
Stefan Janos is a Slovak-Swiss university
physicist
and professor
, founder
of very low temperature physics in Slovakia.
and Zahorska Ves
and between 1958–1961 the high school
in Malacky
. Thereafter he studied at the Czech Technical University, Faculty of Technical and Nuclear Physics in Prague. In 1966 he graduated from university with diploma thesis “ Specific heat of Fe
Co
alloys in the temperature range
1.4 to 4.2 K
. He spent his one-year military service mainly at the Research and Test Centre of the Ministry of Defence in Brno. In August 1967 he joined Faculty of Science at Pavol Jozef Safarik University in Kosice. There he started to build a new laboratory for very low temperature physics. Three years later he spent a study visit in Prof. Boris. N. Eselson laboratory in B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine in Charkov . He participated in experiments on the influence of 3He-atoms on the superfluid state of 4He at 0.5 K. In 1972 he worked at the Aalto University of Helsinki
in Prof. Olli Lounasmaa
Low Temperature Laboratory in Otaniemi
. Finland
. Together with Yuri D. Anufriev he participated in experiments on the search for superfluid state in 3He using Pomeranchuk cooling. He received his PhD
in physics from P.J. Safarik University, Kosice, in 1976 under the supervision of Prof. Vladimir Hajko. His dissertation dealt with the magnon
heat transfer
in thulium and erbium-yttrium
alloys between 0.4 K and 4.2 K and in magnetic fields up to 3 Tesla
. From 1980 to1984 he was head of the Department of Low Temperature Physics in the Institute of Experimental Physics of the Slovak Academy
of Sciences (SAS) in Kosice. His main research interests concentrated on superfluid 3He, nuclear cooling, point-contact spectroscopy
and cryogenic applications in ophthalmology
, gynaecology
and plastic surgery
. He constructed various cryogenic apparatus for cryosurgery
. In 1982 he habilitated on thermal conductivity of Ce, Pr, Nd, Sm, Eu
in the temperature range from 0.5 K to 10 K. Between 1984 and 1990 he worked at the Faculty of Mathematics, Physics and Informatics of the Comenius University in Bratislava
. He held lectures on optics and low temperature physics. His scientific research focused on superfluid 3He and high-temperature superconducting thin REBaCuO films ( RE = Y ,Dy, Ho, Gd, Sm, Nd, Eu
) ]]).
. On 15 June 1990, as an assistant professor, he joined the Laboratory for High Energy Physics of the University of Bern in Switzerland, which was headed by Prof. Klaus Pretzl. He took a leading role in the development of the SSG (Superconducting superheated granules) detector for low energy neutrinos and dark matter
. He took part in experiments using neutron
beam
to study nuclear recoil on Sn, Zn and Al
nuclei conducted at the Paul Scherrer Institute in Switzerland
. In his scientific work at the Laboratory for High Energy Physics in Bern he studied phase transition in Sn, Zn, In, and Al granules and also Al- and In- microstructures using SQUID
( Superconducting Quantum Interference Device). He took a leading role in the development, construction and installation of the ORPHEUS detector for dark matter search in the Bern Underground Laboratory,
. He held exercises and lectures for students of physics
on mechanics
, electricity
, magnetism
and modern physics
. He also lectured on Superfluidity, Superconductivity
and physical properties of solids at low temperatures.
He participated in the discovery of the Lazarus Effect
(1997), which consists in the functional recovery of the silicon detectors exposed to heavy radiation.
On March 1, 2004 he was appointed professor at the University of Bern. From 2006 to 2009 he worked at the Laboratory for High Energy Physics on the design and installation of a central liquid argon
system. Additionally he was deeply involved in the construction of cryostat
s with high vacuum
systems for Time Projection Chamber
s and design of so-called Argontube to study very long (a few meters) electron
drifts in liquid argon .,
. He retired on February 1, 2009.
In 2003 he was awarded Dionyz Ilkovic
Honorary Badge of the Slovak Academy of Sciences for his achievements in low temperature physics and for the development of superconducting detectors for particle physics.
In 2009 he was awarded the Gold Medal of the Faculty of Science of the Pavol Jozef Safarik University in Kosice for his contribution to the development of the faculty, the establishment of the Low Temperature Laboratory and for his efforts in education.
At the occasion of the 40-th anniversary of the Institute of Experimental Physics SAS in Kosice, he obtained the Gold Badge for his contributions to the scientific development of the Institute of Experimental Physics, SAS.
Stefan Janos is honorary member of the Slovak Physical Society.
University
A university is an institution of higher education and research, which grants academic degrees in a variety of subjects. A university is an organisation that provides both undergraduate education and postgraduate education...
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...
and professor
Professor
A professor is a scholarly teacher; the precise meaning of the term varies by country. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences; a teacher of high rank...
, founder
Entrepreneur
An entrepreneur is an owner or manager of a business enterprise who makes money through risk and initiative.The term was originally a loanword from French and was first defined by the Irish-French economist Richard Cantillon. Entrepreneur in English is a term applied to a person who is willing to...
of very low temperature physics in Slovakia.
Life
Between 1950–1958 he attended the primary school in SuchohradSuchohrad
Suchograd is a village and municipality in Malacky District in the Bratislava Region of western Slovakia close to the town of Malacky, north-west of Slovakia's capital Bratislava.-External links:*http://www.statistics.sk/mosmis/eng/run.html...
and Zahorska Ves
Záhorská Ves
Záhorská Ves is a village situated north of Bratislava, the capital city of Slovakia. It is part of the Malacky District and Bratislava Region. The village is located on the Morava river, which forms the border between Slovakia and Austria...
and between 1958–1961 the high school
High school
High school is a term used in parts of the English speaking world to describe institutions which provide all or part of secondary education. The term is often incorporated into the name of such institutions....
in Malacky
Malacky
Malacky is a town and municipality in western Slovakia around 35 km north from capital Bratislava. From the second half of the 10th century until 1918, it was part of the Kingdom of Hungary...
. Thereafter he studied at the Czech Technical University, Faculty of Technical and Nuclear Physics in Prague. In 1966 he graduated from university with diploma thesis “ Specific heat of Fe
FE
Fe or FE may refer to:* Iron * Fe , the f-rune of the Younger Futhark* Fe * Fe * "Fe" , a song by Jorge González...
Co
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....
alloys in the temperature range
Temperature range
Atmospheric temperature range is the numerical difference between the minimum and maximum values of temperature observed in a given location....
1.4 to 4.2 K
Kelvin
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...
. He spent his one-year military service mainly at the Research and Test Centre of the Ministry of Defence in Brno. In August 1967 he joined Faculty of Science at Pavol Jozef Safarik University in Kosice. There he started to build a new laboratory for very low temperature physics. Three years later he spent a study visit in Prof. Boris. N. Eselson laboratory in B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine in Charkov . He participated in experiments on the influence of 3He-atoms on the superfluid state of 4He at 0.5 K. In 1972 he worked at the Aalto University of Helsinki
Aalto University
Aalto University is a Finnish university established on January 1, 2010, by the merger of the Helsinki University of Technology, the Helsinki School of Economics, and the University of Art and Design Helsinki....
in Prof. Olli Lounasmaa
Olli Lounasmaa
Olli Viktor Lounasmaa was a Finnish academician, experimental physicist and neuroscientist...
Low Temperature Laboratory in Otaniemi
Otaniemi
Otaniemi , or Otnäs , is a district of Espoo, Finland. It is located near the border of Helsinki, the capital of Finland....
. Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
. Together with Yuri D. Anufriev he participated in experiments on the search for superfluid state in 3He using Pomeranchuk cooling. He received his PhD
PHD
PHD may refer to:*Ph.D., a doctorate of philosophy*Ph.D. , a 1980s British group*PHD finger, a protein sequence*PHD Mountain Software, an outdoor clothing and equipment company*PhD Docbook renderer, an XML renderer...
in physics from P.J. Safarik University, Kosice, in 1976 under the supervision of Prof. Vladimir Hajko. His dissertation dealt with the magnon
Magnon
A magnon is a collective excitation of the electrons' spin structure in a crystal lattice. In contrast, a phonon is a collective excitation of the crystal lattice atoms or ions. In the equivalent wave picture of quantum mechanics, a magnon can be viewed as a quantized spin wave. As a...
heat transfer
Heat transfer
Heat transfer is a discipline of thermal engineering that concerns the exchange of thermal energy from one physical system to another. Heat transfer is classified into various mechanisms, such as heat conduction, convection, thermal radiation, and phase-change transfer...
in thulium and erbium-yttrium
Rare earth element
As defined by IUPAC, rare earth elements or rare earth metals are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium...
alloys between 0.4 K and 4.2 K and in magnetic fields up to 3 Tesla
Tesla (unit)
The tesla is the SI derived unit of magnetic field B . One tesla is equal to one weber per square meter, and it was defined in 1960 in honour of the inventor, physicist, and electrical engineer Nikola Tesla...
. From 1980 to1984 he was head of the Department of Low Temperature Physics in the Institute of Experimental Physics of the Slovak Academy
Slovak Academy of Sciences
The Slovak Academy of Sciences SAV is the main scientific and research institution in Slovakia fostering basic and strategic basic research...
of Sciences (SAS) in Kosice. His main research interests concentrated on superfluid 3He, nuclear cooling, point-contact spectroscopy
Spectroscopy
Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...
and cryogenic applications in ophthalmology
Ophthalmology
Ophthalmology is the branch of medicine that deals with the anatomy, physiology and diseases of the eye. An ophthalmologist is a specialist in medical and surgical eye problems...
, gynaecology
Gynaecology
Gynaecology or gynecology is the medical practice dealing with the health of the female reproductive system . Literally, outside medicine, it means "the science of women"...
and plastic surgery
Plastic surgery
Plastic surgery is a medical specialty concerned with the correction or restoration of form and function. Though cosmetic or aesthetic surgery is the best-known kind of plastic surgery, most plastic surgery is not cosmetic: plastic surgery includes many types of reconstructive surgery, hand...
. He constructed various cryogenic apparatus for cryosurgery
Cryosurgery
Cryosurgery is the application of extreme cold to destroy abnormal or diseased tissue. The term comes from the Greek words cryo and surgery meaning "hand work" or "handiwork"....
. In 1982 he habilitated on thermal conductivity of Ce, Pr, Nd, Sm, Eu
Rare earth element
As defined by IUPAC, rare earth elements or rare earth metals are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium...
in the temperature range from 0.5 K to 10 K. Between 1984 and 1990 he worked at the Faculty of Mathematics, Physics and Informatics of the Comenius University in Bratislava
Comenius University in Bratislava
Comenius University in Bratislava is the largest university in Slovakia, with most of its faculties located in Bratislava. It was founded in 1919, shortly after the creation of Czechoslovakia. It is named after Jan Amos Comenius, a 17th century Czech teacher and philosopher.In 2006, Comenius...
. He held lectures on optics and low temperature physics. His scientific research focused on superfluid 3He and high-temperature superconducting thin REBaCuO films ( RE = Y ,Dy, Ho, Gd, Sm, Nd, Eu
Rare earth element
As defined by IUPAC, rare earth elements or rare earth metals are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium...
) ]]).
. On 15 June 1990, as an assistant professor, he joined the Laboratory for High Energy Physics of the University of Bern in Switzerland, which was headed by Prof. Klaus Pretzl. He took a leading role in the development of the SSG (Superconducting superheated granules) detector for low energy neutrinos and dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...
. He took part in experiments using neutron
Neutron
The neutron is a subatomic hadron particle which has the symbol or , no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of...
beam
Charged particle beam
A charged particle beam is a spatially localized group of electrically charged particles that have approximately the same velocity . The kinetic energies of the particles are typically measured in keV or MeV, much larger than the energies of particles at ambient temperature...
to study nuclear recoil on Sn, Zn and Al
Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...
nuclei conducted at the Paul Scherrer Institute in Switzerland
Paul Scherrer Institute
The Paul Scherrer Institute is a multi-disciplinary research institute which belongs to the Swiss ETH-Komplex covering also the ETH Zurich and EPFL...
. In his scientific work at the Laboratory for High Energy Physics in Bern he studied phase transition in Sn, Zn, In, and Al granules and also Al- and In- microstructures using SQUID
SQUID
A SQUID is a very sensitive magnetometer used to measure extremely weak magnetic fields, based on superconducting loops containing Josephson junctions....
( Superconducting Quantum Interference Device). He took a leading role in the development, construction and installation of the ORPHEUS detector for dark matter search in the Bern Underground Laboratory,
. He held exercises and lectures for students of physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
on mechanics
Mechanics
Mechanics is the branch of physics concerned with the behavior of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment....
, electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
, magnetism
Magnetism
Magnetism is a property of materials that respond at an atomic or subatomic level to an applied magnetic field. Ferromagnetism is the strongest and most familiar type of magnetism. It is responsible for the behavior of permanent magnets, which produce their own persistent magnetic fields, as well...
and modern physics
Modern physics
The term modern physics refers to the post-Newtonian conception of physics. The term implies that classical descriptions of phenomena are lacking, and that an accurate, "modern", description of reality requires theories to incorporate elements of quantum mechanics or Einsteinian relativity, or both...
. He also lectured on Superfluidity, 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...
and physical properties of solids at low temperatures.
He participated in the discovery of the Lazarus Effect
Lazarus effect
When semiconductor detectors are used in harsh radiation environments, defects begin to appear in the semiconductor crystal lattice as atoms become displaced because of the interaction with the high-energy traversing particles...
(1997), which consists in the functional recovery of the silicon detectors exposed to heavy radiation.
On March 1, 2004 he was appointed professor at the University of Bern. From 2006 to 2009 he worked at the Laboratory for High Energy Physics on the design and installation of a central liquid argon
Argon
Argon is a chemical element represented by the symbol Ar. Argon has atomic number 18 and is the third element in group 18 of the periodic table . Argon is the third most common gas in the Earth's atmosphere, at 0.93%, making it more common than carbon dioxide...
system. Additionally he was deeply involved in the construction of cryostat
Cryostat
A cryostat is a device used to maintain cold cryogenic temperatures. Low temperatures may be maintained within a cryostat by using various refrigeration methods, most commonly using cryogenic fluid bath such as liquid helium. Hence it is usually assembled into a vessel, similar in construction...
s with high vacuum
Vacuum
In everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...
systems for Time Projection Chamber
Time projection chamber
In physics, a time projection chamber is a particle detector invented by David R. Nygren, an American physicist, at Lawrence Berkeley Laboratory in the late 1970s...
s and design of so-called Argontube to study very long (a few meters) electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...
drifts in liquid argon .,
. He retired on February 1, 2009.
Awards
In 1988 he was the co-recipient of the Prize of Slovak Academy of Sciences for the applications of point-contact spectroscopy below 1K.In 2003 he was awarded Dionyz Ilkovic
Dionýz Ilkovič
Dionýz Ilkovič was a Slovak physicist and physical chemist. Along with Jaroslav Heyrovský, he helped to establish theoretical basis of polarography. In this field, he is an author of an important result, called Ilkovič equation. He was also one of the leading figures in modern university-level...
Honorary Badge of the Slovak Academy of Sciences for his achievements in low temperature physics and for the development of superconducting detectors for particle physics.
In 2009 he was awarded the Gold Medal of the Faculty of Science of the Pavol Jozef Safarik University in Kosice for his contribution to the development of the faculty, the establishment of the Low Temperature Laboratory and for his efforts in education.
At the occasion of the 40-th anniversary of the Institute of Experimental Physics SAS in Kosice, he obtained the Gold Badge for his contributions to the scientific development of the Institute of Experimental Physics, SAS.
Stefan Janos is honorary member of the Slovak Physical Society.
Work
- Books in English
- Vladimir. Hajko, et al.: Physics in experiments / 1997, ISBN 80-224-0483-7 view(co-author)
- Books in Slovak
External links
See also
- List of Swiss scientists
- List of Slovak Physicists