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Updated: Aug 9, 2025
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Carrier Lifetime Measurements in Semiconductors through the Microwave Photoconductivity Decay Method
Published on: April 18, 2019
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Nonlinear optical properties and carrier recombination lifetime of GaN
Applied Optics
|February 23, 2023
Abstract:
Nonlinear optical properties of a selection of gallium nitride samples have been measured using picosecond and nanosecond duration laser pulses at 532 nm. The values of the two-photon absorption coefficient, free carrier absorption cross section, and free carrier refraction cross section are determined along with the recombination lifetime of photogenerated carriers. The effect of hot isostatic pressing on these properties in samples with linear absorption at the band edge due to defects is explored.
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Carrier generation is the process by which electron-hole pairs (EHPs) are created within the semiconductor. In direct-bandgap semiconductors, such as gallium arsenide (GaAs), this occurs efficiently when energy absorption prompts valence electrons to leap into the conduction band, leaving behind holes.
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
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01:20Types of Semiconductors
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01:16Biasing of P-N Junction
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01:21Carrier Transport
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Drift Current:
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