Semiconductors: the Energy Gap Between the Valence and Conduction Bands

question 21

Multiple Choice

Semiconductors: The energy gap between the valence and conduction bands in a certain semiconductor is 1.25 eV. What is the threshold wavelength for optical absorption in this substance? (c = 3.00 × 10⁸ m/s, 1 eV = 1.60 × 10^-19 J, h = 6.626 × 10^-34 J ∙ s)

• A) 599 nm
• B) 639 nm
• C) 959 nm
• D) 873 nm
• E) 994 nm

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