A light emitting diode (LED) is fabricated using GaAs semiconducting material whose band gap is 1.42 eV. The wavelength of light emitted from the LED is :
- 1243 nm
- 875 nm
- 650 nm
- 1400 nm
Answer
(2) 875 nm
Solution
The photon energy equals the band gap: Eg = hc
= hcEg = 1240 eV nm1.42 eV
873 nm 875 nm
Answer: (2)