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1. Explain why an indirect bandgap semiconductor is not considered “good” optical semiconductor. 2. Explain why...

1. Explain why an indirect bandgap semiconductor is not considered “good” optical semiconductor.
2. Explain why a direct bandgap semiconductor is considered a “good” optical semiconductor.
3. Explain what a phonon is and explain why they are important for electron transitions between conduction and valence bands in indirect bandgap semiconductors.
4. Explain what is meant by a “radiative transition” and a “non-radiative transition” in semiconductors.

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