E. C. Stoner (physicist) explained

Edmund Stoner
Birth Name:Edmund Clifton Stoner
Birth Date:1899 11, df=yes
Birth Place:Surrey, England
Death Place:Leeds, England
Fields:Magnetism
Astrophysics
Workplaces:University of Leeds
Alma Mater:University of Cambridge
Doctoral Advisor:Ernest Rutherford[1]
Known For:Stoner criterion
Stoner–Wohlfarth model
Independent discovery of Chandrasekhar limit
Awards:Fellow of the Royal Society[2]
Faraday Medal (1955)

Edmund Clifton Stoner FRS (2 October 1899 – 27 December 1968) was a British theoretical physicist. He is principally known for his work on the origin and nature of itinerant ferromagnetism (the type of ferromagnetic behaviour associated with pure transition metals like cobalt, nickel, and iron), including the collective electron theory of ferromagnetism and the Stoner criterion for ferromagnetism.[3] [4] [5] [6] [7] [8] Stoner made significant contributions to the electron configurations in the periodic table.[9] [10] [11]

Biography

Stoner was born in Esher, Surrey, the son of cricketer Arthur Hallett Stoner. He won a scholarship to Bolton School (1911–1918) and then attended University of Cambridge in 1918, graduating in 1921. After graduation, he worked at the Cavendish Laboratory on the absorption of X-rays by matter and electron energy levels; his 1924 paper on this subject prefigured the Pauli exclusion principle.[12] [13] Stoner was appointed a Lecturer in the Department of Physics at the University of Leeds in 1932, becoming Professor of Theoretical Physics in 1939. Starting in 1938, he developed the collective electron theory of ferromagnetism. From 1951 to 1963, he held the Cavendish Chair of Physics.[14] He retired in 1963.

He did some early work in astrophysics and independently computed the (Chandrasekhar) limit for the mass of a white dwarf[15] one year before Subrahmanyan Chandrasekhar in 1931.[16] Stoner calculation was based on earlier work from Wilhelm Anderson on the Fermi gas[17] and on earlier observations of Ralph H. Fowler on white dwarfs.[18] [19] Stoner also derived a pressure–density equation of state for the stars in 1932.[20] These equations were also previously published by the Soviet physicist Yakov Frenkel in 1928. However Frenkel's work was ignored by the astronomical community.[21]

Stoner had been diagnosed with diabetes in 1919. He controlled it with diet until 1927, when insulin treatment became available.

Stoner model of ferromagnetism

See main article: Stoner criterion. Electron bands can spontaneously split into up and down spins. This happens if the relative gain in exchange interaction (the interaction of electrons via the Pauli exclusion principle) is larger than the loss in kinetic energy.

\epsilon\uparrow(k)=\epsilon0(k)-I

n\uparrow-n\downarrow
n

\epsilon\downarrow(k)=\epsilon0(k)+I

n\uparrow-n\downarrow
n

where

\epsilon0(k)

is the energy of the metal before exchange effects are included,

\epsilon\uparrow

and

\epsilon\downarrow

are the energies of the spin up and down electron bands respectively. The Stoner parameter which is a measure of the strength of the exchange correlation is denoted

I

, the number of electrons is

n=n\uparrow+n\downarrow

. Finally,

k

is the wavenumber as the electrons bands are in wavenumber-space. If more electrons favour one of the states, this will create ferromagnetism. The electrons obey Fermi–Dirac statistics so when the above formulas are summed over all

k

-space, the Stoner criterion for ferromagnetism can be established.

Awards and honors

Selected publications

Books

Notes and References

  1. Cantor. Geoffrey. The Making of a British Theoretical Physicist: E. C. Stoner's Early Career. The British Journal for the History of Science. 27. 3. September 1994. 10.1017/S0007087400032180.
  2. Bates . L. F. . 10.1098/rsbm.1969.0011 . Edmund Clifton Stoner 1899-1968 . . 15 . 201–226 . 1969 .
  3. Stoner . E. C. . Collective Electron Ferromagnetism. II. Energy and Specific Heat . 10.1098/rspa.1939.0003 . Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences . 169 . 938 . 339–371 . 1939 . 1939RSPSA.169..339S .
  4. Stoner . E. C. . Collective Electron Ferromagnetism . 10.1098/rspa.1938.0066 . Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences . 165 . 922 . 372–414 . 1938 . 1938RSPSA.165..372S .
  5. Stoner . E. C. . Collective Electron Specific Heat and Spin Paramagnetism in Metals . 10.1098/rspa.1936.0075 . Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences . 154 . 883 . 656–678 . 1936 . 1936RSPSA.154..656S . free .
  6. Stoner . E. C. . The Temperature Dependence of Free Electron Susceptibility . 10.1098/rspa.1935.0214 . Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences . 152 . 877 . 672–692 . 1935 . 1935RSPSA.152..672S . free .
  7. Stoner . E. C. . Martin . L. H. . 10.1098/rspa.1925.0026 . The Absorption of X-Rays . Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences . 107 . 742 . 312 . 1925 . 1925RSPSA.107..312S . free .
  8. Ahmad . N. . Stoner . E. C. . 10.1098/rspa.1924.0050 . On the Absorption and Scattering of Formula-Rays . Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences . 106 . 735 . 8 . 1924 . 1924RSPSA.106....8A . free .
  9. Kragh, Helge. “Niels Bohr’s Second Atomic Theory.” Historical Studies in the Physical Sciences, vol. 10, University of California Press, 1979, pp. 123–86, https://doi.org/10.2307/27757389.
  10. Manjit Kumar, Quantum: Einstein, Bohr and the Great Debate About the Nature of Reality, 2008.
  11. Stoner. Edmund C.. 1924. LXXIII. The distribution of electrons among atomic levels. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. en. 48. 286. 719–736. 10.1080/14786442408634535. 1941-5982.
  12. Wolfgang Pauli. Exclusion principle and quantum mechanics. Online available via ⟨http://nobelprize.org⟩. Nobel Lecture delivered on December 13th 1946 for the 1945 Nobel Prize in Physics.
  13. Manjit Kumar, Quantum: Einstein, Bohr and the Great Debate About the Nature of Reality, 2008.
  14. Web site: uitrbl . Who was E.C. Stoner? . 2022-07-04 . Condensed Matter Physics Group . en-GB.
  15. Stoner. Edmund C.. 1929. V.The limiting density in white dwarf stars. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. en. 7. 41. 63–70. 10.1080/14786440108564713. 1941-5982.
  16. Chandrasekhar. S.. 1931. The Maximum Mass of Ideal White Dwarfs. The Astrophysical Journal. en. 74. 81. 10.1086/143324. 0004-637X. 1931ApJ....74...81C. free.
  17. Anderson. Wilhelm. 1929. Über die Grenzdichte der Materie und der Energie. Zeitschrift für Physik. de. 56. 11–12. 851–856. 10.1007/bf01340146. 1434-6001. 1929ZPhy...56..851A. 122576829.
  18. Journal for the History of Astronomy. Nauenberg, Michael. Edmund C. Stoner and the Discovery of the Maximum Mass of White Dwarfs. 39. 297–312. 2008. 3 . 2008JHA....39..297N. 10.1177/002182860803900302. 43792649 .
  19. Blackman. Eric. 2006. Giants of physics found white-dwarf mass limits. Nature. En. 440. 7081. 148. 10.1038/440148d. 16525442. 0028-0836. free. 2006Natur.440..148B.
  20. Stoner. E. C.. Eddington. A. S.. 1932-05-13. The Minimum Pressure of a Degenerate Electron Gas. Monthly Notices of the Royal Astronomical Society. en. 92. 7. 651–661. 10.1093/mnras/92.7.651. 0035-8711. free. 1932MNRAS..92..651S.
  21. Yakovlev. Dmitrii G. 1994-06-30. The article by Ya I Frenkel' on 'binding forces' and the theory of white dwarfs. Physics-Uspekhi. 37. 6. 609–612. 10.1070/pu1994v037n06abeh000031. 1063-7869. 1994PhyU...37..609Y. 122454024 .
  22. Bates . Leslie Fleetwood . 1969 . Edmund Clifton Stoner, 1899-1968 . Biographical Memoirs of Fellows of the Royal Society . en . 15 . 201–237 . 10.1098/rsbm.1969.0011 . 71746877 . 0080-4606.
  23. http://www.stoner.leeds.ac.uk/about/stoner Edmund Clifton Stoner

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