Edmund Clifton Stoner

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.[2][3][4][5][6][7]

This article is about the Britsh theoretical physicist. For the American illustrator and comics artist, see E.C. Stoner.

Professor Edmund Stoner
Born
Edmund Clifton Stoner

(1899-11-02)2 November 1899
Surrey, England
Died27 December 1968(1968-12-27) (aged 69)
Leeds, England[1]
Alma materUniversity of Cambridge
Known forStoner criterion
Stoner–Wohlfarth model
Independent discovery of Chandrasekhar limit
AwardsFellow of the Royal Society[1]
Scientific career
FieldsMagnetism
Astrophysics
InstitutionsUniversity of Leeds

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. 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.[8] He retired in 1963.

He did some early work in astrophysics and independently computed the (Chandrasekhar) limit for the mass of a white dwarf[9] one year before Subrahmanyan Chandrasekhar in 1931.[10] Stoner calculation was based on earlier work from Wilhelm Anderson on the Fermi gas[11] and on earlier observations of Ralph H. Fowler on white dwarfs.[12][13] Stoner also derived a pressure–density equation of state for the stars in 1932.[14] These equations were also previously published by the Soviet physicist Yakov Frenkel in 1928. However Frenkel's work was ignored by the astronomical community.[15]

Stoner had been diagnosed with diabetes in 1919. He controlled it with diet until 1927, when insulin treatment became available.[1]

Stoner model of ferromagnetism
Main article: Stoner criterion
A schematic band structure for the Stoner model of ferromagnetism. An exchange interaction has split the energy of states with different spins, and states near the Fermi level are spin-polarized.

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.

where is the energy of the metal before exchange effects are included, and 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 , the number of electrons is . Finally, 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 -space, the Stoner criterion for ferromagnetism can be established.

Awards and honors

Selected publications
  • Stoner, Edmund C. (1924). "LXXIII. The distribution of electrons among atomic levels". The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. 48 (286): 719–736. doi:10.1080/14786442408634535. ISSN 1941-5982.
  • Stoner, Edmund C. (1929). "V.The limiting density in white dwarf stars". The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. 7 (41): 63–70. doi:10.1080/14786440108564713. ISSN 1941-5982.[9]
  • Stoner, Edmund C. (1930). "LXXXVII.The equilibrium of dense stars". The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. 9 (60): 944–963. doi:10.1080/14786443008565066. ISSN 1941-5982.
  • Stoner, Edmund C. (1951). "Collective electron ferromagnetism in metals and alloys". Journal de Physique et le Radium. 12 (3): 372–388. doi:10.1051/jphysrad:01951001203037200.

Books

References
  1. Bates, L. F. (1969). "Edmund Clifton Stoner 1899-1968". Biographical Memoirs of Fellows of the Royal Society. 15: 201–226. doi:10.1098/rsbm.1969.0011.
  2. Stoner, E. C. (1939). "Collective Electron Ferromagnetism. II. Energy and Specific Heat". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 169 (938): 339–371. Bibcode:1939RSPSA.169..339S. doi:10.1098/rspa.1939.0003.
  3. Stoner, E. C. (1938). "Collective Electron Ferromagnetism". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 165 (922): 372–414. Bibcode:1938RSPSA.165..372S. doi:10.1098/rspa.1938.0066.
  4. Stoner, E. C. (1936). "Collective Electron Specific Heat and Spin Paramagnetism in Metals". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 154 (883): 656–678. Bibcode:1936RSPSA.154..656S. doi:10.1098/rspa.1936.0075.
  5. Stoner, E. C. (1935). "The Temperature Dependence of Free Electron Susceptibility". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 152 (877): 672–692. Bibcode:1935RSPSA.152..672S. doi:10.1098/rspa.1935.0214.
  6. Stoner, E. C.; Martin, L. H. (1925). "The Absorption of X-Rays". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 107 (742): 312. Bibcode:1925RSPSA.107..312S. doi:10.1098/rspa.1925.0026.
  7. Ahmad, N.; Stoner, E. C. (1924). "On the Absorption and Scattering of Formula-Rays". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 106 (735): 8. Bibcode:1924RSPSA.106....8A. doi:10.1098/rspa.1924.0050.
  8. "About us". School of Physics and Astronomy. University of Leeds. Retrieved 23 October 2017.
  9. Stoner, Edmund C. (1929). "V.The limiting density in white dwarf stars". The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. 7 (41): 63–70. doi:10.1080/14786440108564713. ISSN 1941-5982.
  10. Chandrasekhar, S. (1931). "The Maximum Mass of Ideal White Dwarfs". The Astrophysical Journal. 74: 81. Bibcode:1931ApJ....74...81C. doi:10.1086/143324. ISSN 0004-637X.
  11. Anderson, Wilhelm (1929). "Über die Grenzdichte der Materie und der Energie". Zeitschrift für Physik (in German). 56 (11–12): 851–856. Bibcode:1929ZPhy...56..851A. doi:10.1007/bf01340146. ISSN 1434-6001. S2CID 122576829.
  12. Nauenberg, Michael (2008). "Edmund C. Stoner and the Discovery of the Maximum Mass of White Dwarfs" (PDF). Journal for the History of Astronomy. 39. pp. 297–312. Bibcode:2008JHA....39..297N. doi:10.1177/002182860803900302.
  13. Blackman, Eric (2006). "Giants of physics found white-dwarf mass limits". Nature. 440 (7081): 148. Bibcode:2006Natur.440..148B. doi:10.1038/440148d. ISSN 0028-0836. PMID 16525442.
  14. Stoner, E. C.; Eddington, A. S. (13 May 1932). "The Minimum Pressure of a Degenerate Electron Gas". Monthly Notices of the Royal Astronomical Society. 92 (7): 651–661. Bibcode:1932MNRAS..92..651S. doi:10.1093/mnras/92.7.651. ISSN 0035-8711.
  15. Yakovlev, Dmitrii G (30 June 1994). "The article by Ya I Frenkel' on 'binding forces' and the theory of white dwarfs". Physics-Uspekhi. 37 (6): 609–612. Bibcode:1994PhyU...37..609Y. doi:10.1070/pu1994v037n06abeh000031. ISSN 1063-7869.
  16. "Library and Archive Catalogue". Royal Society. Retrieved 22 October 2010.
  17. Edmund Clifton Stoner, web page at the University of Leeds. Retrieved 21 December 2008.
  18. List of papers, collection at the Leeds University Library. Retrieved 18 January 2007.
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