PAP 514 Frontiers of Modern Physics July 31

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Graduate Lecture Series 29 June 3 July,
2009 Prof Ngee-Pong Chang
Quantum Physics Underlying Modern Technology
Lecture 1 Quantum Physics Overview
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NanoScience
A SCANNING microscope image of platinum-lace
nanoballs. Liposomes aggregate, providing a
foamlike template for a platinum sheet to grow.
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5 x 5 mm image 50 nm Z scale
Nano-scale Tic-Tac-Toe scratched into
polycarbonateLine widths are 40 nm
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Quantum Dots
10-6 m
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Max Planck 1858 - 1947
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A plaque at Humboldt University, Berlin,
commemorating Max Planck as "discoverer of the
elementary quantum of action h," who "taught in
this building" from 1889 to 1928
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Old-fashioned Fireplace
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Progress of Technology Replacing the real
messy with the clean convenient
Log in the Fireplace
Superlog
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Blackbody Radiation
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?max dependence on T
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Wiens Law 1893
1864 - 1928
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Rayleigh-Jeans Law 1900
1842 - 1919
1877 - 1046
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Birth of Quantum Physics
M. Planck, Annalen der Physik, vol 4, 553 (1901)
Blackbody Radiation
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What is quantized ?
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Ideal Blackbody
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Standing Waves in a Cavity
Polarization vector
2 Polarization states
Standing Wave condition
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Standing Wave Condition
or
octant
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Average Energy
Boltzmann Probability Distribution
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Equipartition Theorem
Ultraviolet Catastrophe !
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Rayleigh-Jeans Law 1900
1842 - 1919
1877 - 1046
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Classical
Planck Quantization
Quantum
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Planck Blackbody Radiation Formula
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Birth of Quantum Physics
M. Planck, Annalen der Physik, vol 4, 553 (1901)
Blackbody Radiation
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Relation to Wiens Constant
Peak Intensity condition
Wiens Constant
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Our Universe as a Blackbody
Far Infra-Red Absolute Spectrophotometer
1997
Cosmic Background Radiation
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FIRAS DATA
2.7280 0.0001 K BLACKBODY
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What is quantized ?
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Albert Einstein 1879 - 1955
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Einsteins Photon Hypothesis (1905)
Energy
Momentum
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Niels Bohr 1885 - 1962
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Bohr Model of the Atom
1913
Angular Momentum Quantization
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Bohr Model of the Atom
Angular Momentum Quantization
Bohr radius
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Bohr Model of the Atom
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Compton wavelength of electron
Fine Structure Constant
Bohr Radius
Hydrogen 1s level
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rst.gsfc.nasa.gov
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Einsteins Photon Hypothesis
Energy
Momentum
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1924
Prince Louis-Victor Pierre Raymond de
Broglie (1892 1987)
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W. Heisenberg 1901 - 1976
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Uncertainty Principle
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A convenient back-of-the-envelope way to keep
track of the energy levels of quantum wells, and
quantum dots.
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E. Schrodinger 1887 - 1961
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Schrodinger Equation
Stationary State
Time-Independent Schrodinger Equation
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Classical Equations of Motion
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Ehrenfest Theorem
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Average Expectation Values
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Paul Ehrenfest 1880 - 1933
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Max Born 1882 - 1970
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Double Slit Experiment
Electron build up over time
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Ehrenfest with his students Dieke, Goudsmit,
Tinbergen, Ehrenfest, Kronig, Fermi.
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George Uhlenbeck 1900 - 1988
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S. Goudsmit 1902 - 1978
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Note to Goudsmit by L.H. Thomas Mar 25, 1926
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Wolfgang Pauli 1900 - 1958
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Pauli Bohr a spinning top
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Dirac Equation
Non-relativistic limit
Spin-Orbit Coupling
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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
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Electron orbiting around nucleus
In electron rest frame, nucleus orbiting around
electron
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Enrico Fermi 1901 - 1954
Paul Dirac 1902 - 1984
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Fermi Sea
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Fermi-Dirac Distribution
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Einstein
Planck
Heisenberg
Schrodinger
Pauli
Bohr
1927 Solvay Conf
Dirac
A. Piccard, E. Henriot, P. Ehrenfest, Ed. Herzen,
Th. De Donder, E. Schrödinger, E. Verschaffelt,
W. Pauli, W. Heisenberg, R.H. Fowler, L.
Brillouin,P. Debye, M. Knudsen, W.L. Bragg,
H.A. Kramers, P.A.M. Dirac, A.H. Compton, L. de
Broglie, M. Born, N. Bohr, I. Langmuir, M.
Planck, M. Curie, H.A. Lorentz, A. Einstein, P.
Langevin, Ch. E. Guye, C.T.R. Wilson, O.W.
Richardson
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Bose Einstein Statistics 1924
1894 - 1974
1879 - 1955
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Kammerlingh Onnes 1853-1926 On the Sudden Rate at
Which the Resistance of Mercury Disappears
Communications of the Leiden Laboratory, 1911
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Meissner Effect 1933
Robert Ochsenfeld
Walther Meissner 1882 - 1974
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Quantization of Flux