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Graduate Lecture Series 29 June – 3 July, 2009 Prof Ngee -Pong Chang

Graduate Lecture Series 29 June – 3 July, 2009 Prof Ngee -Pong Chang. Lecture 4 Electron Spin. George Uhlenbeck 1900 - 1988. S. Goudsmit 1902 - 1978. Pieter Zeeman 1865 - 1943.

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Graduate Lecture Series 29 June – 3 July, 2009 Prof Ngee -Pong Chang

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  1. Graduate Lecture Series 29 June – 3 July, 2009 Prof Ngee-Pong Chang Lecture 4 Electron Spin

  2. George Uhlenbeck 1900 - 1988

  3. S. Goudsmit 1902 - 1978

  4. Pieter Zeeman 1865 - 1943

  5. Photo taken by Zeeman of the splitting of the spectral lines in intense magnetic field. Reported on Saturday, October 31, 1896 at the meeting of the Royal Netherlands Academy of Arts and Sciences in Amsterdam, where these results were communicated by KamerlinghOnnes. The next Monday, Lorentz called Zeeman in his office and presented him with an explanation of his observations, based on Lorentz' theory of electromagnetic radiation.

  6. Hendrik A Lorentz 1853 - 1928

  7. Relationship between Magnetic Moment and Orbital Angular Momentum

  8. Zeeman Effect Larmor Precession

  9. Anomalous Zeeman effect Photo taken by Zeeman of the splitting of the spectral lines in intense magnetic field. Reported on Saturday, October 31, 1896 at the meeting of the Royal Netherlands Academy of Arts and Sciences in Amsterdam, where these results were communicated by KamerlinghOnnes. The next Monday, Lorentz called Zeeman in his office and presented him with an explanation of his observations, based on Lorentz' theory of electromagnetic radiation.

  10. Anomalous Zeeman Effect

  11. Classical radius of the electron

  12. Classical picture of electron spin !!!!! Compton wavelength Of the electron

  13. Paul Ehrenfest 1880 - 1933

  14. G.E. Uhlenbeck and S. Goudsmit, Naturwissenschaften 47 (1925) 953. A subsequent publication by the same authors, Nature 117 (1926) 264, is followed by a very interesting postscript by N. Bohr. See: http://www.lorentz.leidenuniv.nl/history/spin/goudsmit.html

  15. Ralph Kronig 1904 - 1995

  16. Wolfgang Pauli 1900 - 1958

  17. Pauli & Bohr & a spinning top

  18. g – factor of the electron

  19. Thomas Precession of electron spin as a general relativity effect Llewellyn H. Thomas 1903-1992

  20. Note to Goudsmit by L.H. Thomas Mar 25, 1926

  21. I think you and Uhlenbeck have been very lucky to get your spinning electron published talked about before Pauli heard of it. It appears that more than a year ago Kronig believed in the spinning electron and worked out something; the first person he showed it to was Pauli. Pauli ridiculed the whole thing so much that the first person became also the last and no one else heard anything of it. Which all goes to show that the infallibility of the Deity does not extend to his self-styled vicar on earth. Note to Goudsmit by L.H. Thomas Mar 25, 1926

  22. Wolfgang Pauli 1900 - 1958

  23. Pauli Spinor Wave Function Denotes electron wave function with spin up Denotes electron wave function with spin down

  24. Pauli Spin Matrices Group Properties

  25. Spin Eigenfunctions

  26. Measured Spin: Relation to Pauli Spin Wave Function Normalization Condition

  27. Spin pointing in other than z-direction

  28. Spin pointing in other than z-direction

  29. Precession of Electron Spin B-field in z-direction

  30. Precession of Electron Spin

  31. Precession of Electron Spin

  32. Precession of Electron Spin

  33. Rotating the Electron Elementary Particles and the Laws of Physics: the 1986 Dirac Memorial Lectures by Richard Feynman, Steven Weinberg

  34. Why does the spin precess when there is No applied B field ?

  35. Origin of Spin-Orbit Coupling Electron moving in a static E field sees a magnetic field, B : Electron spin precesses around this B field according to the magnetic moment interaction

  36. Electron orbiting around nucleus In electron rest frame, nucleus orbiting around electron

  37. Why does the spin precess when there is No applied B field ? Electron sees a B-field when it moves in a Voltage gate Origin of the Rashba term for spin-orbit coupling

  38. Spintronicsberlin lecture michaelihulsen spin-fet Slide 9.

  39. Spintronicsberlin lecture michaelihulsen spin-fet Slide 11.

  40. Spintronicsberlin lecture michaelihulsen spin-fet Slide 22.

  41. Spintronicsberlin lecture michaelihulsen spin-fet Slide 12.

  42. SpintronicsDatta-Das Spin Field Effect Transistor Precession controlled by Voltage gate Das Sarma RMP v76 00323 (2004) fig. 1

  43. Das Sarma American Scientist v89, 516 (2001), Fig 3

  44. Spintronics ferro insulator Ferromagnetic tunneling Das Sarma RMP v76 2004 00323, fig. 2

  45. Das SarmaAmerican Scientist v89, 516 (2001), Fig 7

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