Introduction to Optical Electronics

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Introduction to Optical Electronics
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Injection Electroluminescence
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Spontaneous Photon Emissionelectron-hole
radiative recombination
Emitted photons (rate ?)
Injected Carriers (rate R)
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Spontaneous Emission
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Electroluminescence
Rate of Spontaneous Emission
Optical Joint Density of States
Conduction Band and Valence Band Energy State
Probability of fulfilling emission condition
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ElectroluminescenceDetermining Fermi Functions
Concentrations of Electrons Holes
Density of States near band edges
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(No Transcript)
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Quasi-Fermi Levels
T 0 K
T gt 0 K
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Exercise 16.1-2 Spectral Density of
Injection Electroluminescence Under Weak
Injection
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Spontaneous Emission Spectral Densityin Thermal
Equilibrium
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Phenomenological Approach to Diode Lasers
taken from Diode Lasers and Photonic Integrated
Circuits, Larry Coldren Scott Corzine, John
Wiley Sons, 1995
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Energy Diagram Heavily Doped p-n Junction
V
0
p
n
Efc
Electron Energy
eV
h?
Efv
Position
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Geometrical Aspects of a p-n Junction
p
n
l1
A
C
B
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Spontaneous Emissions (LED)
Figure 2.3 Schematic of LED showing how only a
small portion of the generatedlight reaches a
desired detector.
taken from Diode Lasers and Photonic Integrated
Circuits, Larry Coldren Scott Corzine, John
Wiley Sons, 1995
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LED Characteristics
Internal Photon Flux
Output Photon Flux
Overall Quantum Efficiency
Responsivity
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Surface-Emitting Lasers
taken from Diode Lasers and Photonic Integrated
Circuits, Larry Coldren Scott Corzine, John
Wiley Sons, 1995
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Phenomenological Approach to Diode Lasers
taken from Diode Lasers and Photonic Integrated
Circuits, Larry Coldren Scott Corzine, John
Wiley Sons, 1995
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PumpingSemiconductor Laser Amplifier
Optical Pumping
Electrical Pumping
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Semiconductor Laser Amplifiers
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Gain
T 0 T gt 0
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Semiconductor Laser Amplifiers
Gain
Amplifier Bandwidth
Approximate Peak Gain Coefficient
Peak Gain Coefficient Electric Pumping
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PumpingSemiconductor Injection Laser
Cleaved Surface
w
_

i
d
l
n
p
Cleaved Surface
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Semiconductor Injection Lasers
Laser Amplification
Feedback
Resonator Loss
Gain Condition Laser Threshold
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Spatial Spread of Laser Light
Refractive Index
x
x
Homostructure Laser
Heterostructure Laser
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Lateral Confinement StructuresHeterostructure
Lasers
taken from Diode Lasers and Photonic Integrated
Circuits, Larry Coldren Scott Corzine, John
Wiley Sons, 1995
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Semiconductor Injection LasersPhoton Flux and
Power
Steady-State Laser Internal Photon Flux
Internal Laser Power
Laser Output Photon Flux
Laser Output Power
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Laser Light-Current CurveStrongly Index-Guided
Buried-Heterostructure
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Spatial Distributions of Optical Intensity
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Diode Laser Output Power vs Current
taken from Diode Lasers and Photonic Integrated
Circuits, Larry Coldren Scott Corzine, John
Wiley Sons, 1995