A `p-n` photodiode is made of a material with a band gap of `2.0 eV`. The minimum frequency of the radiation that can be absorbed by the material is nearly

Options

A. `10xx10^(14)Hz`
B. `5xx10^(14)Hz`
C. `1xx10^(14)Hz`
D. `20xx10^(14)Hz`

Answer

B

Explanation

p-n photodiode is a semiconductor diode that produces a significant current when illuminated, it is reversed biased but is operated below the breakdown voltage.
Energy of radiation = band gap energy
i.e. `hv =2.0 eV`
`or v=(2.0xx1.6xx10^(-19))/(6.6xx10^(-34))=5xx10^(14) Hz`