Robert Wichard Pohl

from Wikipedia, the free encyclopedia
Robert Wichard Pohl, 1923 in Göttingen
Göttingen city cemetery grave of Prof. Otto Wilhelm Madelung and Prof. Robert Wichard Pohl

Robert Wichard Pohl (born August 10, 1884 in Hamburg , † June 5, 1976 in Göttingen ) was a German physicist . He is known for his experimental physics lecture, which was also published as a textbook, and as a pioneer of solid state physics . Nevill Francis Mott even described him as the "true father of solid state physics".

The Pohl wheel is named after Robert Wichard Pohl .

Youth and Studies

Robert Wichard Pohl was born in Hamburg as the son of the shipbuilding engineer Eugen Robert Pohl and his wife Martha, daughter of Wichard Lange , the founder of the private school Dr. Wichard Lange, and granddaughter of Wilhelm Middendorff , who founded the first German kindergarten together with Friedrich Froebel .

After visiting the Dr. Wichard Lange Schule, he entered the learned school of the Johanneum in 1895 , which he left with the Abitur in 1903 to study natural sciences in Heidelberg in the 1903 summer semester . There he met James Franck , with whom he was a close friend until his death in 1964. In the winter semester of 1903 he went to the University of Berlin to study physics. As early as the summer semester of 1904 he was working in the Physics Institute under Emil Warburg on the subject that became his doctoral thesis. It was there that his first publication came about, inspired by Bernhard Walter from the Hamburg State Physical Laboratory, where he subsequently worked during the holidays, primarily looking for X-ray diffraction.

Monorail: RWP shows the stabilization with the help of a gyro (monorail) (RW Pohl, Mechanik . (All conditions))

Career up to the First World War

In the summer of 1906 he was promoted to Dr. phil. PhD and then taught as an assistant in the physical internship under the director of the Heinrich Rubens Institute . They worked together with James Franck on ion mobility in gases and on the question of the speed of X-rays. From 1909 he worked on the normal and the selective photoelectric effect of metals, from 1910 together with Peter Pringsheim , including the practically important work on the production of metal mirrors. In 1910 a monograph on the remote transmission of images was published and in 1912 he received his habilitation . In an addendum, the habilitation thesis contains a discussion of Laue's discovery of X-ray diffraction.

After completing his habilitation, Pohl began to give experimental physics lectures, which he also used to create a private collection of demonstration instruments. He also performed experiments in meetings of the Physical Society. By the beginning of the war, he had published 54 papers in addition to the three books.

When the war broke out, Pohl tried in vain to be accepted as a volunteer, but was turned down for health reasons. , Along with his offer Erich Regener set up in two spare hospitals from their own resources X-ray equipment and operate, was gratefully accepted. At the beginning of November he found the opportunity to work with the radio operators on the discovery of enemy broadcasting stations. This resulted in a position as chief engineer with the traffic engineering examination commission (VPK) in the captain's rank, which he filled out until the end of the war.

Chair in Göttingen

In February 1916 he was appointed to Göttingen as associate professor (and successor to Eduard Riecke ), but was only able to take up the professorship at the beginning of 1919 because of the war. Heinrich Rausch von Traubenberg represented him at this time. In his moving luggage there were more than 40 boxes filled with equipment for his lectures. Due to a call to the Technical University of Stuttgart in September 1919, he received a regular full professorship in Göttingen in December 1920 and became director of the 1st Physics Institute. In June 1922 an offer from Würzburg followed, which he refused. In the heyday of physics in Göttingen in the 1920s, he had one of the three professorships for physics alongside James Franck (director of the 2nd Physics Institute) and the theoretical physicist Max Born .

At Christmas 1922 he married Tussa Madelung, the sister of Erwin Madelung , who had been an assistant at the Physics Institute in Göttingen when Tussa and her family moved from Strasbourg to Göttingen in May 1920. They had three children: Ottilie, Eleonore and Robert Otto , later professor of physics at Cornell University .

n- and p-line: visualization to the left of the n-line (through electrons, green) and right of the p-line (through defect electrons, brown) in a KI crystal. Cathode (left) and anode (right) are Pt tips fused into the crystal. RW Pohl, Electricity , from the 10th edition (1944) on.

Photoelectric observations - not on surfaces like in Berlin, but inside insulators - began Pohl with his assistant Bernhard Gudden in 1919. (The work of this period is described in detail in (first part) .) So they discovered that diamond Crystals became electrically conductive when illuminated. They then observed the same effect in the alkali halide sodium chloride , but only after it had taken on a color due to exposure to X-ray light. A systematic investigation of these color centers on artificially produced crystals led to the discovery of the color centers , which were subsequently examined in detail. By installing three electrodes in a potassium bromide crystal, Rudolf Hilsch was able to show the first model of a transistor with color centers in 1938 .

In addition to this work in his institute, he also helped his scientific colleagues in their work. With the zoologist Alfred Kühn he examined the bees' sense of color, for the chemist Adolf Windaus he used optical spectroscopy to separate ergosterol from cholesterol . He helped the archaeologist Kurt Müller to photograph antique vases without annoying reflections. He actively supported his student Hans Joachim Pabst von Ohain when he made the first attempts at jet propulsion with his own resources at the institute following his dissertation .

Introductory lecture in physics

The introductory lecture in physics was very important to him from the start, and he kept describing new experiments in scientific journals that he had devised for this purpose and which he then used in his textbooks. The first book of his famous introduction to physics, " Electricity ", was published in 1927. In 1930, " Mechanics and Acoustics " was published, the third edition expanded by " Heat ". The third volume, the " Optics ", was published in 1941, the ninth edition of which was expanded in 1954 to include " Atomic Physics ".

Bright spatial interference field shown on the lecture hall wall (RW Pohl, "Optik", since 2nd edition 1941, also "Elektrizitätslehre und Optik" )

The work at the Göttingen Institute is summarized in a new chapter “Quantum Optics of Solid Bodies” . The 15th edition (1955) of the "Electricity Theory" also deals with the electrical properties of solid bodies, including the results of his Göttingen work. After his death, the three volumes were reduced to two, with these chapters removed. Both volumes now contain videos with a total of 110 experiments performed with the original devices. The second volume also contains a video with a biography of Pohl, authored by Ekkehard Sieker. Further videos in the same volume show the current amplification in a three-electrode crystal as well as an audio recording of the awarding of an honorary doctorate to Ernest Rutherford by Dean Max Born (1931).

Post war time and appreciation

Pohl described his attitude towards the Nazi regime in a résumé at the request of the military government. (Second part) After that he never belonged to a political party, was reserved or hostile to the National Socialists (he had contacts with the Goerdeler -kreis, his contact, the teacher Hermann Kaiser, was executed in January 1945) and was from the beginning of the Second World War on convinced of a defeat Germany. After the war he worked until 1948 as a member of the denazification committee on the reconstruction of the University of Göttingen.

The work of the Pohl Institute only became known abroad shortly before the outbreak of war, when Pohl and his assistant Hilsch were invited to a conference in Bristol in 1937 on The conduction of electricity in solids . The first comprehensive publication on color centers appeared in the USA in 1946. In 1951 she was invited to Urbana at the University of Illinois with visits to the Bell Telephone Laboratories , the Naval Research Laboratory and other research institutions. On this occasion he met Franck again, after Franck's forced emigration in 1933 their friendship was renewed. In 1956 the first International Color Center Conference took place at the Argonne National Laboratory , which was followed every three years in the following years up to 1977.

Pohl has always kept his institute small. Of his 55 German doctoral students, 11 later became full professors at a German university, and of his 7 foreign doctoral students, 6 received professorships abroad.

The importance of the Göttingen work was summarized in 1980 by Nobel Prize winner Nevill Mott :

"RW Pohl of Göttingen is in my view the real father of solid state physics."

After his retirement in 1952, he continued to work on his textbooks. In an interview with his former student Heinz Pick in 1974, Pohl described some of his other experiences in Göttingen in detail.

Awards

  • 1921 Academy of Sciences in Göttingen , member
  • 1928 Technical University of Wroclaw, Dr. – Ing. e. H.
  • 1935 Leopoldina , Halle, member
  • 1937 German Academy of Aviation Research, member
  • 1939 University of Sofia, Dr. hc
  • 1945 Photographic Society in Vienna, Golden Society Medal
  • 1949 Bavarian Academy of Sciences , corresponding member
  • 1950 Heidelberg Academy of Sciences , corresponding member
  • 1953 American Association of Physics Teachers, Honorary Membership
  • 1954 Federal Republic of Germany, Great Cross of Merit
  • 1957 Technical University of Darmstadt, Dr. rer. nat. hc
  • 1959 American Association of Physics Teachers, Oersted Medal
  • 1959 University of Göttingen, Dr. med. hc
  • 1964 University of Hamburg, Dr. rer. nat. hc
  • 1967 Federal Republic of Germany, Grand Cross of Merit with Star
  • 1971 Medal of Honor from the City of Göttingen
  • 1975 German Society for Chronometry, Phillip Matthäus Hahn plaque

The Robert Wichard Pohl Prize for Experimental Physics and Physics Didactics, awarded by the German Physical Society , is named after him . In addition, the Robert Wichard Pohl Institute at Tongji University, Shanghai , which is supported by the Volkswagenwerk Foundation, has been named after him since 1979 . Since 1995 he is at his house in Göttingen, Klopstockstr. 4, a plaque. Since 2007 the Faculty of Physics at the University of Göttingen has also been awarding the Robert Wichard Pohl Medal to lecturers for the best teaching performance.

Textbooks

  • Introduction to Physics , Springer Verlag, Berlin (three-volume edition)
    • part 1
      • Mechanics and Acoustics , (1st edition 1930, 2nd edition 1931)
      • Mechanics, acoustics and thermodynamics , (3rd / 4th edition 1941 - 18th edition (RO Pohl, ed.) 1983)
    • Volume 2
      • Electricity , (1st edition, 1927 - 21st edition, 1975)
    • Volume 3
      • Optik , (1st edition 1940 - 8th edition 1948)
      • Optics and Atomic Physics , (9th edition 1954 - 13th edition 1976)
  • Introduction to Physics , Springer Verlag, Berlin (two-volume edition)
    • part 1
      • Mechanics, acoustics and thermodynamics , (K. Lüders and RO Pohl, eds.) (19th edition, 2004, 20th edition 2009, 21st edition 2017)
    • Volume 2
      • Electricity theory and optics , (K. Lüders and RO Pohl, eds.) (22nd edition 2006, 23rd edition 2010, 24th edition 2018)
    • Both volumes were also published as English translations in 2017 and 2018, respectively.

Engagements (selection)

Pohl supported the reform pedagogical school by the sea on the North Sea island of Juist, founded and directed by Martin Luserke , with a generous donation of a large number of musical instruments for the school orchestra led by Eduard Zuckmayer and the music hall of the only school theater hall in Germany at the time .

Robert Wichard Pohl Medal

The ' (also short Pohl Medal' ) is a prize named after him that has been awarded in the Faculty of Physics at the Georg-August-Universität Göttingen to professors and young scientists for outstanding achievements in teaching, usually in the As part of a lecture in the previous semester . The award is made by the study commission , a commission of the faculty council , on the basis of the course evaluations of the previous semester.

Award winners

The winners of the Pohl Medal are:

Semester 1 Name of the award winner Reason for the award 2
WS 2019/2020 Fabian Heidrich-Meisner Quantum Mechanics I
SS 2019 no award
WS 2018/2019 Stefan Klumpp continuously outstanding teaching achievements
SS 2018 no award
WS 2017/2018 Oliver Boghun continuously outstanding teaching achievements
SS 2017 Stefan Mathias Introduction to solid state physics
WS 2016/2017 no award
SS 2016 Stanley Lai Statistical Methods of Data Analysis
WS 2015/2016 Florian Rehfeldt continuously outstanding teaching achievements
WS 2015/2016 Eckart Modrow Medal of Honor for years of commitment to introducing programming in the natural sciences
SS 2015 Karl-Henning Rehren Analytical mechanics
WS 2014/2015 Stefan Kehrein
SS 2014 Steffen Schumann
WS 2013/2014 Kevin Kröninger continuously outstanding performance
SS 2013 no award
WS 2012/2013 no award
SS 2012 no award
WS 2011/2012 Ariane Frey Introduction to nuclear and particle physics
SS 2011 Kurt Schönhammer Quantum Mechanics I
SS 2011 Richard Vink Computer simulation methods in statistical physics (award for young scientists)
WS 2010/2011 Thomas Pruschke Mathematical methods of physics
SS 2010 Claus Ropers continuously positively evaluated events (prize for young researchers)
SS 2010 Lecture preparation team Medal of Honor
WS 2009/2010 Hans-Ulrich Krebs Introduction to solid state and material physics
WS 2009/2010 Cynthia A. Volkert Introduction to solid state and material physics
SS 2009 Matthias Sperl Mathematics for physicists
SS 2009 Sarah Köster Mechanics of the Cell (Prize for Young Scientists)
WS 2008/2009 Andreas Honecker Analytical mechanics
SS 2008 Karl-Henning Rehren Quantum Mechanics I
SS 2008 Ansgar Reiners Stellar activity and brown dwarfs, low-mass stars, etc. Planets (Prize for Young Scientists)
WS 2007/2008 Detlev Buchholz exceptional teaching achievements
1 WS is the name for the winter semester and SS the name for the summer semester .
2 Unless otherwise stated, this is the name of the lecture in which the lecturer in question had an outstanding teaching performance in the previous semester.

literature

  • “ Göttingen Histories for the First Physics Institute ” , collected by Manfred Achilles, 2012, (also contains many references to biographical literature about RW Pohl).
  • Roland Wittje: "Simplex Sigillum Veri": Robert Pohl and Demonstration Experiments in Physics after the Great War , in: Peter Heering, Roland Wittje (Ed.) "Learning by Doing", Franz Steiner Verlag, 2011.
  • Jürgen Teichmann : " The music of facts ", Physik Journal 8, p. 45 (2009), online
  • Jürgen Teichmann:  Pohl, Robert Wichard. In: New German Biography (NDB). Volume 20, Duncker & Humblot, Berlin 2001, ISBN 3-428-00201-6 , p. 586 f. ( Digitized version ).
  • Frederick Seitz , Norman G. Objection: " Electronic Genie ", University of Illinois Press, 1998, chapter 4
  • Gisela Oittner-Torkar, Jürgen Teichmann: “ The explanation of the real crystal by Robert Wichard Pohl ”, in: Karl von Meyenn (Ed.) “ The Great Physicists ”, Volume 2: from Maxwell to Gell-Mann , Munich: Beck 1997, p 170-177
  • Lillian Hoddeson , Ernest Braun, Jürgen Teichmann, Spencer Weart (editors): Out of the crystal maze. Chapters from the history of solid state physics , Oxford University Press 1992
  • Georg Busch: Early History of the Physics and Chemistry of Semiconductors , European Journal of Physics, Vol. 10 (1989), pp. 255-265
  • Jürgen Teichmann : On the history of solid state physics, color center research until 1940 , Steiner Verl., Stuttgart (1988)
  • Michael Eckert , Helmut Schubert: crystals, electrons, transistors , Rowohlt Taschenbuch Verlag, Reinbek 1986, pp. 115–128
  • Hans-Joachim Queisser : Kristallene Krisen , Piper Verl. Munich, (1985), pp. 66-80
  • The Beginnings of Solid State Physics , a symposium organized by Sir Nevill Mott, ed., Proceedings of the Royal Society London A, Volume 371 (1980)
  • Hans von Ohain : The Evolution and Future of Aeropropulsion Systems , in: Walter J. Boyne and Donald S. Lopez (Eds.): The Jet Age, Smithsonian Institution Press (1979), pp. 25-46
  • Heinz Pick: Structure of trapped electron and trapped hole centers in alkali halide “color centers” , in: F. Abeles (Ed.) “Optical Properties of Solids”, North-Holland Publishing, Amsterdam (1972), pp. 654-754 .

Web links

Commons : Robert Wichard Pohl  - Collection of images, videos and audio files

Individual evidence

  1. ^ A b Neville Mott: "Bristol Physics in the 1930", Chapter in RG Chambers, M. Hart (Ed.), "Histories of Physics in Bristol", 2005. See also "Components of the Solid State", New Scientist, Volume 69, 1960, No. 993, pp. 663-666
  2. ↑ "On the Effect of Silent Electrical Discharge on Ammonia and Oxygen", R. Pohl, Negotiations of the German Physical Society , VIII. Volume No. 2 (1906), p. 11, and inaugural dissertation with the same title (1906)
  3. ↑ “About the glow when gases are ionized. On the interpretation of the experiments of Mr. B. Walter ”, R. Pohl, Annalen der Physik 4th part (1905), Volume 17, p. 375
  4. ↑ "Further experiments on the diffraction of X-rays", B. Walter and R. Pohl, Annalen der Physik Volume 29 (1909), p. 331
  5. ↑ a b "The photoelectric phenomena", R. Pohl and P. Pringsheim, Verlag Friedr. Vieweg & Son, Braunschweig 1914
  6. ^ "About the production of metal mirrors by distillation in a vacuum", negotiations of the German Physical Society, Volume 14 (1912), p. 506
  7. ^ A b "The electrical remote transmission of images", R. Pohl, Verlag Friedr. Vieweg & Son, Braunschweig 1910
  8. ↑ a b "The Physics of X-rays", R. Pohl, Verlag Friedr. Vieweg & Son, Braunschweig 1912
  9. ↑ Meeting on November 20, 1914: “… Furthermore, Mr. R. Pohl some lecture attempts ”. Negotiations of the German Physical Society, November 30, 1914
  10. ↑ a b c Biographical notes by Robert Wichard Pohl: "Memories of the beginnings of solid state physics in Göttingen and the curriculum vitae and political position of RW Pohl" , R. Pohl and H. Pick
  11. ↑ "About photoelectric conductivity of diamonds", B. Gudden and R. Pohl, September 1919 Zeitschrift für Physik Volume 3, 1920, p. 123
  12. ↑ "A method for the production of large crystals", S. Kyropoulos, Zeitschrift für inorganic und Allgemeine Chemie Volume 154 (1926), p. 308
  13. ↑ a b “Comprehensive report on electron conduction and photochemical processes in alkali halide crystals”, R. Pohl, Physikalische Zeitschrift Volume 39, 1938, pp. 36–54
  14. ↑ a b "Control of electron currents with a three-electrode crystal and a model of a barrier layer", R. Hilsch and R. Pohl, Zeitschrift für Physik Volume 111, 1938, p. 399
  15. ^ "Bees' ability to train on spectral lines", A. Kühn and R. Pohl, Die Naturwissenschaften Volume 9, 1921, p. 1
  16. ^ "For the optical detection of a vitamin", R. Pohl, Die Naturwissenschaften , Volume 15 (1927), p. 433
  17. ^ "About avoiding disturbing reflexes when taking photos of Greek vases", Kurt Müller, Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen, Classical Studies , Volume II, No. 5 (1937), p. 103
  18. ↑ "My love was pure physics" (PDF; 2.1 MB), conversation with HJ Pabst von Ohain, Georgia Augusta University of Göttingen, spectrum, volume 2, 1995, p. 10
  19. ↑ Ekkehard Sieker, "Simplex Sigillum Veri", Vol. 2. Video 1
  20. ↑ From the foreword to vol. 2, 22nd edition, see 24th edition, 2018, p. VII.
  21. ↑ Frederick Seitz, "Color Centers in Alkali Halide Crystals", Reviews of Modern Physics, Volume 18, 1946, p. 384. Part II, Volume 26, 1954, p. 7.
  22. ↑ Florian Ebner, "James Franck - Robert Wichard Pohl, Briefwechsel 1906 - 1964", Deutsches Museum preprint, issue 8 ( http://www.deutsches-museum.de/verlag/aus-der-forschung/preprint )
  23. ↑ H. Pick, "Fifty years of color center physics", Journal de physique, Colloque C6, Supplement to no.7, Volume 41, 1980, pp. C6-1
  24. ↑ RWPohl, Memory Colloquium, 29. Nov. 1976 (MusterSchmidt Verlag, Göttingen) :: Address by the Rector of the Georg-August University . S. 9 .
  25. ↑ Website of the University of Göttingen ( https://www.uni-goettingen.de/de/robert-wichard-pohl-medaille/471232.html )
  26. ^ Logbook of the Schule am Meer Juist, entry from April 22, 1932
  27. ↑ a b Website of the University of Göttingen.Retrieved on December 12, 2015
personal data
SURNAME Pohl, Robert Wichard
BRIEF DESCRIPTION German physicist
DATE OF BIRTH August 10, 1884
PLACE OF BIRTH Hamburg
DATE OF DEATH 5th June 1976
Place of death Goettingen