The quantum efficiency (η) and responsivity (R) at a wavelength λ (in μm) in a p-i-n photodetector are related by

R = η×λ/1.24
R = λ/(η×1.24)
R = 1.24×λ/η
R = 1.24/(η×λ)

Correct answer: R = η×λ/1.24

Solution

The correct option expresses the relationship between quantum efficiency and responsivity, indicating that responsivity is directly proportional to quantum efficiency and the wavelength, while being inversely proportional to a constant factor (1.24), which accounts for the conversion between energy and wavelength.

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