Optical Processes in Semiconductors: Review

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Optical Processes in Semiconductors Review

• A. Aydinli

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PL

• Emission of optical radiation resulting from
  excitation to a nonequilibrium state by
  irradiation with light.
• Create electron-hole pairs by absorption of
  exciting light
• Radiative recombination of electron-hole pairs
• Escape of recombination radiation from the
  sample.

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PL

• Sensitive (compared to absorption)
• Nondestructive
• Simple to perform
• Considerable analysis may be required to reach
  the physical mechanism

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Electron-Photon Interaction

• Solve
• To obtain

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Fermis Golden Rule

• Interaction energy between the radiation field
  and atomic system can be written either

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Absorption/Emission
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DOS
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Transitions in Bulk
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Emission vs Gain
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Direct Gap Absorption
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Direct Gap Absorption
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Absorption in QW
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Population Inversion in a QW
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Intersubband Absorption
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Intersubband Absorption
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Inter- and intraimpurity Transitions
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Free-bound
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Band-band
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Degeneracy