Question

Find the maximum wavelength of electromagnetic radiation which can create a hole-electron pair in germanium. The band gap in germanium is 0.65 eV.

Answer 1

Answer:

We know

$E = \frac{hc}{ \lambda} \\ \\ \lambda = \frac{E}{hc}$

Given

$E = 0.65 \times 1.6\times {10}^{ -1 9} \: j \\ h = 6.63 \times {10}^{ - 34} \: js \\ c = 3 \times {10}^{8} \: m {s}^{ - 1}$

So

$\lambda = \frac{0.65 \times {10}^{ - 34} }{6.63 \times {10}^{ - 19} \times 3 \times {10}^{8} } \: m \\ \\ \lambda \approx3.2 \times {10}^{ - 25} \: m$