A p-type semoconductor has acceptor levels `57meV `above the valence band. Find the maximum wavelength of light which can create a hole.

Explanation

`E=(hc)/lambda r lambda=(hc)/E=(6.62 times 10^(-34) times 3 times 10^(8))/(57 times 10^(-3) times 1.6 times 10^(-19))`
`=217100A " or " E=12400/lambda`
(E is in eV and `lambda` is in A)