Introduction to Optical Electronics

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Introduction to Optical Electronics
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Optics
Ray Optics (Geometrical Optics)

• Focus on location direction of light rays
• Limit of Wave Optics where ? 0

Wave Optics (Gaussian Beam)

• Scalar wave theory (Single scalar wavefunction
  describes light)

EM Optics (Geometrical Optics)

• Two mutually coupled vector waves (E M)

Quantum Optics (Photon Optics)

• Describes certain optical phenomena that
  arecharacteristically quantum mechanical

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Chronological Development of Optics

• Michael Faraday (1791 1867)
• James Clerk Maxwell (1831 1879)
• James Bradley (1693 1762)
• Dominque Arago (1786 1853)
• Augustin Jean Fresnel (1788 1827)
• Armand Fizeau (1819 1896)
• Airy (1801 1892)
• Henrik Antoon Lorentz (1853 1928)
• Albert Abraham Michelson (1852 1931)
• Jules Henri Poincare (1854 1921)
• Albert Einstein (1879 1955)
• Max Planck (1858 1947)
• Richard Phillips Feynman (1918 1988)

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The Photoelectric Effect
A
V

1. The photoelectric current is proportional to the
   intensity of the radiation
2. Photoelectric emission starts with no observable
   time lag after illumination starts, even if the
   intensity is very low
3. The maximum kinetic energy of the emitted
   electrons is independent of the intensity of the
   light
4. There is a linear relation between the stopping
   potential (V0) and frequency (?) for any given
   metal

The stopping potential V0 is defined as the
magnitude of the potential difference necessary
to reduce the current to zero.
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Moving from Wave to Particle Nature of Light

• Wave Nature of Light(Classical)
• Light in resonator
• completely characterized by EM field

• Particle Nature of Light(Quantum)
• Light in resonator
• comprised of a set of modes containing an
  integral number of photons
• Characteristics of the modes taken from classical
  and assigned to photon
• ?
• spatial distribution
• direction of propagation
• polarization

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Photon (Quantum) Optics

• Photons
• Energy
• Position
• Momentum
• Polarization
• Interference
• Time

• Photon Streams
• Coherent
• Partially Coherent
• Probability Rules!
• Mean Photon Flux
• Photon-Number Statistics
• Random Partitioning

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Blackbody Radiation Theory
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Density of Modes
ky
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Light as Particles - Photons

• Energy
• Position
• Momentum
• Polarization
• Interference
• Time

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Quantum Effects
I
?
I
?
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Photon StreamsStatistics!
Temporal
Spatial
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Photon Flux

• Mean Photon-Flux Density
• Mean Photon Flux
• Mean Number of Photons

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Classical vice Quantum Concepts
Spectral Definitions
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Photon FluxTime-Varying

• Mean Photon-Flux Density
• Mean Photon Flux
• Mean Number of Photons

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Uncertainty Relationships
Defining Conjugate Pairs
Uncertainty
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More Uncertainty Relationships
More Conjugate Pairs
Uncertainty
Conjugate Heisenbergs Pairs Uncertainty
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Photon-Number StatisticsCoherent Light
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Photon-Number Statistics

• Coherent Light

Poisson Distribution
Mean Variance
Signal-to-Noise Ratio
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Photon-Number StatisticsThermal Light
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Photon-Number Statistics

• Thermal Light
• Boltzman Prob. Dist.

Bose-Einstein Distribution
Mean Variance
Signal-to-Noise Ratio
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Atom Photon Interactions
Next Class!