Talk:Indirect bandgap
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Is this entirely correct: "Indirect bandgap semiconductors can absorb light, however this only occurs for photons with significantly more energy than the bandgap."
Couldn't an indirect semiconductor absorb a photon with the bandgap energy, if the momentum vector of the photon was just right? --User:Dgrant
- No, because the momentum of a photon is very small compared to the momentum offset between CB and VB. Radiative transitions appear as very nearly vertical lines on the E-k diagram. Radiative recombination and emission is possible with the help of a well-placed phonon, but such events are very unlikely. In practice, conduction band electrons in silicon are de-excited via traps. -- Tim
E-k space
Can someone explain what the E-k space / k-vector is? I don't get it. Thanks, --Abdull 12:14, 30 May 2005 (UTC)